On November 25, 2018, Russian coast guard vessels in the Black Sea forcibly prevented two small Ukrainian armored artillery boats and a tugboat from transiting the Kerch Strait en route to the Ukrainian port of Berdyansk, on the Sea of Azov, according to official Ukrainian and Russian reports (see Figure 1). After ramming the tugboat and blockading all three boats for hours, the Russian vessels reportedly fired on them as they sought to leave the area, injuring six sailors. The Ukrainian boats and their 24 crew members were detained and taken to Kerch, in the Russian-occupied Ukrainian region of Crimea. The sailors were arrested and placed in pretrial detention on charges of illegally crossing what Russia refers to as its state border (i.e., the territorial waters around occupied Crimea). Observers generally viewed the incident as a major escalation of tensions between Russia and Ukraine.
In May 2018, Russian President Vladimir Putin opened a new 12-mile-long bridge linking Russia to Crimea over the Kerch Strait, the waterway connecting the Black Sea to the Sea of Azov. The bridge was designed to accommodate an existing shipping lane, but it imposes new limits on the size of ships that transit the strait.
Observers note that since the bridge's opening, Russia has stepped up its interference with commercial traffic traveling to and from Ukrainian ports in Mariupol and Berdyansk, which export steel, grain, and coal. Russian authorities reportedly have imposed delays at the bridge and conducted inspections of vessels. Russian authorities also have established notification and transit procedures for ships seeking to pass through the strait; during the November 25 incident, Russian authorities invoked what they considered noncompliance with these procedures as partial justification for denying the Ukrainian boats passage.
Since the bridge opened, Russia and Ukraine have bolstered their maritime forces in the Sea of Azov. For Russia, this has included transferring to the area (via an inland waterway) naval ships previously assigned to a flotilla in the Caspian Sea. The Ukrainian artillery boats that attempted to transit the Kerch Strait on November 25 were the second pair of naval ships to pass through the strait; a command ship and tugboat crossed in September 2018, escorted by Russian coast guard vessels (other Ukrainian ships have arrived over land).
A 2003 bilateral agreement between Ukraine and Russia affirms freedom of navigation through the strait for both countries (it might be argued that customary international law as reflected in the United Nations Charter on the Law of the Sea, or UNCLOS, also does that). According to Ukrainian officials, the agreement allows for Russian inspections, since it recognizes the Sea of Azov as shared "inland waters." Although Ukrainian officials have considered withdrawing from the agreement, some observers believe this could further disadvantage Ukraine, since Russia could use its de facto control over Crimea and the Kerch Strait to assert sovereignty over most of the Sea of Azov and further restrict Ukrainian and third-party access.
Ukraine is seeking the return of its sailors and ships. It also seeks to call attention to what it considers a major escalation in Russia's efforts to control access to the Sea of Azov. Ukrainians are particularly concerned that Russia's actions could lead to a blockade of Ukraine's eastern territories and possibly expanded military operations on land.
Source: Congressional Research Service.
The Ukrainian government introduced 30 days of martial law from November 28, 2018, in regions of the country bordering Russia, the Black Sea and Sea of Azov, and Moldova (where Russian troops are stationed in the separatist region of Transnistria). During the period of martial law, reportedly, the administrative border with Crimea is to remain closed to non-Ukrainian passport holders and Russian male nationals are to be barred from entering Ukraine.
The United States and much of the international community rejects Russia's claims to sovereignty over Crimea and, by extension, surrounding waters. The United States and the European Union (EU) have called on Russia to release the Ukrainian sailors, return the vessels, and restore freedom of passage through the strait; they also called Russia's actions a violation of international law. On November 27, 2018, the Senate passed S.Res. 709, condemning Russia's actions and calling on the Trump Administration "to implement an all-of-government approach to forcefully express opposition to the ... attack ... at every opportunity." In response to the incident, according to the White House, President Trump canceled a meeting with President Putin at the recent G-20 summit in Buenos Aires.
Observers debate what additional steps, if any, the United States and/or the EU should take in response. Some have called for imposing additional sanctions on Russia. Ukrainian officials and some observers have called on the United States and NATO to increase their maritime presence in the Black Sea and Sea of Azov (although only smaller warships would be physically able to pass through the strait, assuming Russia did not block their passage). A NATO spokesperson noted that NATO already has increased its presence in the Black Sea and "will continue to assess our presence in the region."
The incident's timing coincides with a recent increase in tensions between Russia and Ukraine due to a new willingness by the Ecumenical Patriarchate of Constantinople to grant the Ukrainian Orthodox Church formal independence (i.e., autocephaly) from the Russian Orthodox Church. Some observers believe such a development could reduce Russian influence in Ukraine. Russia strongly opposes such a move.
Domestic political considerations in Russia and Ukraine also may have played a role. In recent months, Russian public support for Putin has visibly declined, with approval ratings as low as 66% (down from over 80% in the last four years); some observers interpret Russia's action as an attempt to boost Putin's popularity. For his part, Ukrainian President Petro Poroshenko faces stiff competition in Ukraine's upcoming presidential election, scheduled for March 31, 2019. Some believe Poroshenko will use the incident—and potentially his strengthened authority under martial law—to his political advantage.