The United States expresses its deep concern over Russia’s plans to block foreign naval ships and state vessels in parts of the Black Sea, including near occupied Crimea and the Kerch Strait. Russia has a history of taking aggressive actions against Ukrainian vessels and impeding access to Ukraine’s ports in the Sea of Azov, impacting Ukraine’s international commerce. This represents yet another unprovoked escalation in Moscow’s ongoing campaign to undermine and destabilize Ukraine. This development is particularly troubling amid credible reports of Russian troop buildup in occupied Crimea and around Ukraine’s borders, now at levels not seen since Russia’s invasion in 2014, and other provocative actions by Russia-led forces at the line of contact.