Russia said on Monday it was “unacceptable” for shipping to pass through a Black Sea security corridor after it suspended its participation in a Turkish- and UN-brokered deal that had allowed Ukraine to resume grain exports.

“The movement of ships along the security corridor is unacceptable since the Ukrainian leadership and the command of the Armed Forces of Ukraine use it to conduct military operations against the Russian Federation,” the Russian defense ministry said in a statement.

“Under the current conditions, there can be no question of guaranteeing the security of any object in the indicated direction until the Ukrainian side accepts additional obligations not to use this route for military purposes.”

It emphasized, however, that Russia was not withdrawing from the deal but only suspending it, in a move that Moscow announced on Saturday after what it said was a Ukrainian drone attack on its Black Sea fleet.

Read: Russian navy ‘repels’ drone attack on Crimea’s Sevastopol port: official

The ministry did not say what Russia would do if ships continued to sail the route. On Monday a record volume of 354,500 tonnes of agricultural products left Ukrainian ports under the grain deal, despite Moscow’s weekend announcement, a spokesperson for Odesa’s military administration said.

The Kremlin said earlier on Monday that without Russian security commitments, the grain deal was “hardly feasible, and it takes on a different character - much more risky, dangerous, and unguaranteed”.

Ukrainian President Volodymyr Zelenskiy has accused Moscow of “blackmailing the world with hunger” by pulling out of the agreement.