Israel-Iran Conflict, U.S. Strikes, and Ceasefire

Updated June 1626, 2025 (IF13032)

On June 13, 2025, Israel began a major military operation against Iran, including air strikes and reported covert action. Prime Minister Benjamin Netanyahu vowed to continue attacks for "as many days as it takes," targeting what he termed "existential" threats posed by Iran's nuclear program and ballistic missiles. Iran's foreign minister described Israel's attack as a "declaration of war" in a letter to the United Nations. Iran has retaliated by launching hundreds of ballistic missiles against Israel amid continued Israeli airstrikes across Iran and international calls for de-escalation.

Israeli attacks reportedly have degraded Iranian air defenses and some missile bases, killed a number of high-level Iranian military and government officials and nuclear scientists, and struck some nuclear sites, government buildings, energy facilities, and other targets across the country (see Figure 1). Strikes and other attacks have reportedly killed over 200 in Iran as of June 15 and 24 in Israel as of June 16. The U.S. military is reportedly helping Israel intercept Iranian missiles in the ongoing conflict, as it did during Iran's April and October 2024 drone and missile attacks. President Trump reportedly has directed additional U.S. air and naval assets toward the region. Israel has procured most of its fighter aircraft and large munitions from U.S. suppliers, financed to date by more than $3 billion of U.S. aid annually.

Figure 1. Reported Israel-Iran Strikes As of June 16, 2025

Source: New York Times. Red points represent strike locations. All areas and notations are approximate and subject to revision and updates.

Congressional and Administration Responses

President Donald Trump said he was aware of the Israeli plans beforehand and supports Israel, and alluded to "more to come" on June 13. Secretary of State Marco Rubio stated at the outset of the Israeli attack that the United States was "not involved" in the strikes. Prior to the strikes, President Trump expressed a preference for a negotiated rather than military solution. President Trump posted on Truth Social that Israel's attacks came at the end of the 60-day deadline he set for U.S.-Iran negotiations to reach a deal when they began in mid-April, and told a reporter the attack might compel Iran to reach an agreement with the United States. Iran canceled a sixth round of talks, previously scheduled for June 15.

President Trump said on June 15 that that the United States is "not at this moment involved" but could be. He has continued to state his hope for a deal on the nuclear issue but noted Israel and Iran may "have to fight it out," and stated openness to potential Israel-Iran mediation by Russia. With Israeli analysts reportedly assessing that Israel has hit only a portion of Iran's nuclear program, some reports indicate that Israel may have asked U.S. officials for participation in an operation against Iran's deep underground enrichment facility at Fordow.

Some Members of Congress expressed support for Israel's actions and called the operation "understandable and justified." Others called the strike "alarming" and "reckless" and expressed concern about possible escalation. On June 16, Senator Tim Kaine introduced a joint resolution directing the President to "terminate the use of United States Armed Forces for hostilities against the Islamic Republic of Iran … unless explicitly authorized by a declaration of war or specific authorization for use of military force against Iran." Congress passed a similar resolution after the January 2020 U.S. strike that killed Islamic Revolutionary Guards Corps-Qods Force (IRGC-QF) Commander Qasem Soleimani; President Trump vetoed that 2020 resolution and a Senate vote to overturn the veto failed of passage.

Historical Background

During Prime Minister Netanyahu's tenure after 2009, Israel has threatened multiple times to act militarily to destroy or set back Iran's nuclear program. Israel, which for decades has presumably maintained a nuclear arsenal but has not officially acknowledged it, has taken preemptive action against nuclear programs in the region—destroying an Iraqi facility in 1981 and a Syrian one in 2007. In the 2010s, IsraelIran retaliated by launching waves of ballistic missiles against Israel. See Figure 1 and Figure 2 for maps depicting strikes on both countries. Israel has procured most of its fighter aircraft and large munitions from U.S. suppliers, financed to date by nearly $4 billion of U.S. aid annually. On June 22, the United States carried out strikes against three key Iranian nuclear sites (see Figure 1), including a deep underground uranium enrichment facility at Fordow. Israeli officials reportedly may have sought direct U.S. involvement in targeting certain Iranian nuclear facilities with specific "bunker buster" bombs and aircraft (the United States used GBU-57 Massive Ordnance Penetrator weapons and B-2 Spirit bombers in its air strikes). In a notification to Congress that President Donald Trump said was "consistent with the War Powers Resolution" (P.L. 93-148), President Trump stated the strike "was taken to advance vital United States national interests, and in collective self-defense of our ally, Israel, by eliminating Iran's nuclear program."

Figure 1. Reported Strikes on Iran

Source: CRS, adapted from CNN (citing The Institute for the Study of War with AEI's Critical Threats Project, U.S. President Donald Trump, International Atomic Energy Agency), as of June 24, 2025.

Notes: All areas and notations are approximate.

Central Intelligence Agency Director John Ratcliffe has stated that some intelligence indicates "several key Iranian nuclear facilities were destroyed and would have to be rebuilt over the course of years." An Iranian official observed that "our nuclear installations have been badly damaged." The director general of the International Atomic Energy Agency said that "very significant damage is expected to have occurred" at Fordow. Broader details regarding the impact on Fordow and other sites may remain unclear. The whereabouts of Iran's uranium stockpiles appear uncertain. It is unclear how the strikes may affect Iran's technical capabilities. It is also unclear whether the strikes may have altered Iran's political decision-making regarding its nuclear program and aspirations toward weaponization.

Figure 2. Reported Strikes on Israel & the West Bank

Source: CRS, adapted from CNN (citing Reuters and CNN analysis of social media), as of June 24, 2025.

Notes: All areas and notations are approximate.

Some Members of Congress expressed support for Israel's military actions and called its operations "understandable and justified." Some have expressed support for H.Res. 521 in favor of U.S. assistance for Israel. Others called the Israeli strikes "alarming" and "reckless." Some introduced resolutions or legislation (S.J.Res. 59, H.Con.Res. 38, S. 2087) emphasizing the role of Congress in authorizing the use of U.S. force. A range of opinions surrounded the U.S. strikes as well, with some Members praising them, and some expressing concern that the strikes raise risks of broader conflict, may not have been as effective as initially asserted, or were based on assessments or decisions that did not sufficiently involve Congress.

On June 23, Iran fired ballistic missiles at Al Udeid Air Base in Qatar, in what may have been a largely symbolic retaliation; no U.S. casualties were reported. Hours later, President Trump announced that Israel and Iran would end hostilities on June 24. After some additional salvos, Israel and Iran indicated intentions to comply with the ceasefire, but reserved the right to defend themselves. President Trump said another U.S. strike could happen if Iran resumed uranium enrichment.

Israeli attacks reportedly degraded several Iranian military, government, and energy facilities, among other targets in Iran, and killed a number of high-level Iranian military and government officials and nuclear scientists. Reports indicate that Israel may have destroyed a significant portion of Iran's ballistic missile launchers. Strikes and other attacks by Israel and Iran have reportedly killed over 600 people in Iran and 29 in Israel.

Historical Background

During Israeli Prime Minister Benjamin Netanyahu's tenure after 2009, Israel has threatened multiple times to act militarily to destroy or set back Iran's nuclear program. Israel, which for decades has reportedly maintained a nuclear arsenal but has not officially acknowledged it, has taken preemptive action against nuclear programs in the region—destroying an Iraqi facility in 1981 and a Syrian one in 2007. In the 2010s, Israel, reportedly with U.S. help in at least one instance, apparently executed a number of covert actions against Iranian facilities and personnel to disrupt and delay the program. Alongside U.S. sanctions on Iranian oil exports, the Obama Administration led international efforts to reach a 2015 agreement (Joint Comprehensive Plan of Action, or JCPOA), which placed new physical constraints, as well as inspection and monitoring provisions, on Iran's nuclear program. In 2018, President Trump (with strong support from Netanyahu) ended U.S. participation in the JCPOA, citing what he described as the accord's defects, and increased sanctions on Iran. Approximately a year later, Iran began nuclear activities that exceeded limits set forth in the JCPOAJCPOA-stated limits.

Hamas-led attacks on Israel in 2023 were followed by broader regional conflict between Israel and Iran's "axis of resistance." Direct clashes between Israel and Iran in April and October 2024 and Israel's large-scale degradation of Hezbollah (a key Iranian ally) in Lebanon prompted serious discussion in Israel about whether and when to act against Iran's nuclear program. Having seemingly mostly neutralized Hezbollah's missile threat and ostensibly weakened Iran's air defenses and ballistic missile production capacity, Israeli leaders reportedly explored plans, including with U.S. counterpartsofficials, to strike Iran's nuclear program amid increasingly public discussion in Iran of the once-taboo subject of weaponization. Some of President Trump's public comments discouraged attacks while U.S. officials engaged in diplomacy with Iran after April 2025.

Iran: Impact and Possible Responses

Leadership. According to Israeli claims and other reports, major Iranian figures killed or injured in the Israeli attack may include its military chief of staff; the commanders of the IRGC, IRGC Air Force, IRGC-Quds Force, and IRGC-Intelligence Organization; an advisor to Supreme Leader Ayatollah Ali Khamenei with responsibility for nuclear negotiations; and at least 10 senior nuclear scientists.

Iran's regime. Israel's assault could inspire Iranians to rally around a government that has faced popular protests in recent years, or could contribute to political instability. Netanyahu said that regime change could be an outcome of Israeli operations. Israel reportedly refrained from a possible opportunity to kill Supreme Leader Khamenei because of opposition from President Trump. Netanyahu declined to discuss the report.

Nuclear program. The impact on Iran's nuclear program may depend on what remains of Iran's enriched uranium stockpiles, accumulated technical knowledge, or other elements of its nuclear program—parts of which are underground and may be less vulnerable to aerial attacks. The International Atomic Energy Agency's Director General reported on June 16 that strikes had "destroyed the above-ground part" of a uranium enrichment facility at Natanz and damaged the Isfahan nuclear site; he also reported that no "damage has been seen" at Fordow, amid some reported attacks near the facility. Iran could pull out of the Nuclear Non-Proliferation Treaty (which Iranian officials had recently threatened to do) and/or accelerate efforts to develop a nuclear weapon to deter or threaten Israel and other adversaries. In March 2025, U.S. officials restated their assessment that Iran does not have a nuclear weapons program, but that added "Iran's enriched uranium stockpile is at its highest levels and is unprecedented for a state without nuclear weapons."

Military responses. It is unclear what additional capabilities Iran might seek to use against Israel. In June 10 House Armed Services Committee testimony, U.S. Central Command Commander General Michael Kurilla said that a U.S. Terminal High Altitude Area Defense system was defending Israel from ballistic missile threats. Iran or its partners could attack U.S. regional installations, having on June 11 reiterated long-standing threats to do so. Iran's foreign minister said that the June 13 attack "could not have been carried out without the coordination and authorization of the United States." Secretary Rubio warned Iran not to target U.S. interests or personnel, some of whom may have started departing the region before the Israeli attacks. Such attacks, or Iranian moves to close the Strait of Hormuz or otherwise disrupt global energy markets, could trigger direct U.S. responses. It is unclear whether Iran's apparent loss of senior military leaders and the damage to weapons and infrastructure could affect its ability to coordinate military attacks. The Wall Street Journal reported on June 16 that Iran has signaled interest in ending hostilities and returning to negotiations as long as the United States does not join attacks on Iran.

Regional and International Reactions

The Gulf Cooperation Council (comprising several Arab states) said that Israel's actions violate international law, and called for concerted international efforts to stop Israel's "aggression" and avoid escalation. Russia and the People's Republic of China also strongly criticized Israel's attack.

Considerations for Congress

In engaging executive branch officials, shaping legislative responses to recent developments, and conducting oversight, Congress could consider the following questions:

• What immediate effect could the conflict have on U.S. citizens and personnel? What, if anything, should the U.S. government do to assist U.S. citizens in the region? How may the conflict affect regional and global security and commerce?
• How has fighting so far affected Iran's nuclear program, military capabilities, and government stability? How have Iranian strikes affected Israel and what has been the U.S. role in combatting them?
• What military responses might Iran consider taking against U.S. personnel and installations? Against U.S. partners? Under what circumstances might the U.S. military become more involved in the conflict?
• How likely are Iranian leaders to attempt to move closer to acquiring nuclear weapons in response? What are the prospects for U.S.-Iran nuclear talks?
• How might fighting between Israel and Iran affect the regional balance of power, great power competition, and U.S. capacity to pursue its strategic priorities in the Indo-Pacific, Europe, and elsewhere?

To support, reject, or modify the Administration's approach to developments, Congress may consider action concerning military assistance, arms sales, sanctions, defense appropriations, authorization of use of military force, diplomacy and negotiated agreements, and oversight of the Administration's past and ongoing policies and programs.