If Europe bans Russian oil and gas imports immediately, the UK will suffer an economic hit of £70bn and enter a recession, Rishi Sunak has told colleagues.
The UK chancellor said a total EU ban would be a disaster for economies across Europe, including the UK, in a cabinet meeting last week, as reported by the Financial Times.
Some 40% of the bloc's gas and 25% of its crude oil comes from Moscow and though the UK imports only 8% of its total oil from Russia it would feel the impact of a severe EU downturn.
The European Central Bank has said that just a 10% reduction in gas supplies would cause 0.7% of GDP to be lost in the eurozone.
Sunak's warning follows a recent call from British Prime Minister Boris Johnson to ban the import of Russian hydrocarbons by western allies, with the EU announcing plans to reduce Russian gas imports by two-thirds within a year.
Last week Downing Street said it planned to phase out all Russian oil over the coming months, with US president Joe Biden also announcing the imposition of sanctions prohibiting imports of Russian oil and gas.
Boris Johnson is expected to unveil a new energy strategy for the UK next week but was warned by the Institute for Government that the country needs a long-term plan to protect households and businesses from high energy costs by reducing energy demand and securing other energy supplies away from Russia.