Russia and Ukraine are in a row over the inland Sea of Azov that they share, with both sides accusing each other of detaining each others' ships illegally. However, no specific example of delaying or preventing access for a ship by Russia has been cited in the UK Foreign Office's statement.
"Russia’s continued disruption of ships attempting to access Ukrainian ports in the Sea of Azov is destabilising the regional economy. Restrictions on freedom of passage have been accompanied by an increase in Russia’s military presence in the sea," the statement read.
"This is causing delays, significant increases in shipping costs, and a reduction in income to Ukraine’s ports. So far, more than 200 vessels have been affected, in a policy which is damaging Ukraine’s economy and undermining its sovereignty," a spokesperson of the office said, as quoted in the statement.
The spokesperson voiced his side's concern over Russia's "growing military presence" in the Sea of Azov. "We call on Russia to allow unhindered access for merchant vessels through the Kerch Strait and in the Sea of Azov," the spokesperson concluded.
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Tensions between Russia and Ukraine in the Sea of Azov rose this year after Ukraine detained two Russian ships for port calls in Russian Crimea, which Ukraine considers as its territory. Russia described the move as "maritime terrorism" and ramped up patrols off its Azov coast, prompting Ukraine to accuse Russia of illegal searches.
The dispute has been brought to attention of the European Union. The EU neighborhood policy commissioner, Johannes Hahn, said during a trip to Kiev that the issue was high on the agenda.