Russia may use sea mines to target civilian shipping in the Black Sea, including by laying them on the approach to Ukrainian ports, the British government said on Wednesday citing intelligence.

Russia pulled out of a deal in July that had allowed Ukraine to safely ship food products out through what is traditionally its main export corridor.

Ukraine responded by setting up a temporary "humanitarian corridor" for cargo vessels, and several ships have left Ukraine's Black Sea ports since.

Britain said its assessment of the intelligence was that Russia was seeking to target civilian shipping traveling through the humanitarian corridor in order to deter the export of Ukrainian grain.

"Russia almost certainly wants to avoid openly sinking civilian ships, instead falsely laying blame on Ukraine for any attacks against civilian vessels in the Black Sea," Britain's Foreign Office said in a statement.

"By releasing our assessment of this intelligence, the U.K. seeks to expose Russia's tactics to deter any such incident from occurring."

Last month Britain accused Russia of targeting a civilian cargo ship at port in the Black Sea on Aug. 24 in a missile attack it said was successfully thwarted by Ukrainian defenses.

Britain said it was working with Ukraine and other partners to put in place arrangements to improve the safety of shipping and was using its intelligence, surveillance, and reconnaissance capabilities to monitor Russian activity in the Black Sea.