Russia is preparing legislation to ban British fishermen from the Barents Sea, one of the biggest fisheries for cod and haddock in the world, according to a major Russian newspaper.

Vladimir Putin’s government is in favour of draft legislation submitted by the agriculture ministry that would see Russia pulling out of a Soviet-era fishing agreement that allowed British vessels to operate in the sea, according to Izvestiya.

The 1956 fisheries agreement came as part of concerted diplomatic efforts to ease post-war tensions with the West, and allowed British vessels to fish for seafood along the coast of the Russian Kola Peninsula, east of Cape Kanin Nos, off Kolguev Island and the small islands in the Barents Sea.

The sea is along the northern coasts of Norway and Russia.

Already fraught relations between the UK and Russia crashed.

Britain has been one of Ukraine’s most important international allies ever since, providing an estimated £12bn in direct support as well as imposing a string of sanctions on Russian entities and businesses.

The bill denouncing the Barents Sea fishing agreement has already been approved by Russia’s cabinet after it was submitted by the agriculture and foreign ministries, according to Izvestiya, and is now with the Kremlin. The legislation would also need to be approved by Russia’s parliament.