President Trump should give the Ukraine “lethal maritime equipment and weapons” in the wake of Russia’s seizure of three Ukrainian naval vessels in a key disputed shipping lane, according to the top Senate Democrat on the Foreign Relations Committee.

“Yesterday’s events show that the Kremlin remains sharply intent on weakening Ukraine’s security and democratic trajectory,” New Jersey Sen. Bob Menendez said in a statement Monday. "In response, the Trump Administration must immediately increase security assistance to Ukraine, including the provision of lethal maritime equipment and weapons.”

Russia seized three small Ukrainian warships late Sunday when the vessels tried to pass through the Kerch Strait into the Sea of Azov, where the Ukrainian port city of Mariupol rests. But Moscow has claimed both sides of the strait — the lone shipping lane that connects Mariupol to the open ocean — ever since the 2014 annexation of Crimea from Ukraine. So Russian security forces fired on the vessels and detained 24 sailors, accusing them over transgressing into Russian territorial waters.

“The Kremlin must immediately return the seized Ukrainian vessels and cease any future actions that threaten the freedom of passage through the Kerch Strait,” Menendez said. “The United States should also assist Ukraine’s efforts to improve its maritime domain awareness. NATO also has a critical role and should consider increasing exercises and its presence in the Black Sea.”

Rep. Eliot Engel, incoming chairman of the House Foreign Affairs Committee, also called for the United States to bolster military support for the Ukrainians.

“Russia continues to isolate itself and set the stage for further unnecessary loss of Ukrainian and Russian life,” the New York lawmaker said in a statement. “The United States and governments around the world must hold Russia accountable for these illegal and dangerous actions and bolster our political and defensive military support for Ukraine.”

Moscow and Kiev have settled into low-grade conflict in eastern Ukraine, where the Kremlin has orchestrated a separatist conflict against the Ukrainian government. And Russian President Vladimir Putin has consolidated control of the Sea of Azov, “an economic blockade, de facto,” as a Baltic diplomat described it to the Washington Examiner — especially following the construction of a bridge across the Kerch Strait, connecting Russia to the Crimean peninsula.

“[Russia is] also looking for a provocation because their actions in Azov Sea make economic business almost impossible for some of the vessels,” the diplomat said during the interview. “So, Azov Sea is a very hot spot right now.”

That conversation took place last week, just a few days before two Ukrainian gunships and a tug vessel tried to pass through the strait over Russia’s objections. "When the Ukrainian side was planning this provocation, they must have calculated the additional benefits they wanted to derive from this situation expecting the U.S. and Europe to blindly support the instigators, as usual,” Russian Foreign Minister Sergey Lavrov said Monday, according to TASS, Russia's state-run outlet.

Engel dismissed Russian criticism of Ukraine’s actions. “Russia has no legitimate territorial claims in this case, yet has again relied on force to trample its neighbors’ sovereignty and flout international law,” he said.