Britain on Monday instructed public sector bodies to review any contracts they have with Russian firms and consider switching suppliers, noting that most existing contracts were for energy and could benefit the Russian state.

Britain is, alongside allies, seeking to cripple the Russian economy through sanctions in response to its invasion of Ukraine.

"Public money should not fund (Russian President Vladimir) Putin’s war machine. We are asking hospitals, councils and other organisations across the public sector to urgently look at all the ways they can go further to sever their commercial ties to Russia," government minister Steve Barclay said in a statement.

The government is searching for alternative energy suppliers to replace Russian gas, which makes up less than 4% of Britain's supply.

The latest advice came in a procurement policy guidance note published on the government website.

"The public sector’s exposure to Russian and Belarusian suppliers is primarily limited to the energy markets, where there have been significant price fluctuations and the market is considered volatile," it said.

"You must seek advice from an energy expert and/or a relevant public sector buying organisation before taking action to terminate an existing energy supply contract to ensure an alternative source of supply is available and affordable."

(Reporting by William James, Editing by Kylie MacLellan)