The strait is the only passage from the Black Sea to the Sea of Azov where Ukraine has seaports.
The United States Mission to the OSCE has called on Russia to cease the blocking of the Kerch Strait.
"We call on Russia to refrain from any further escalatory actions and immediately take the necessary steps to de-escalate tensions in the region, including by rescinding its actions to block certain vessels in parts of the Black Sea, by recommitting to a ceasefire in the Donbas, and by ceasing all its destabilizing activity in Ukraine," chief of Mission, Courtney Austrian, told the Permanent Council in Vienna April 29.
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