UK ministers last week gained powers to impose tough new sanctions on Russian oligarchs and businesses.

Prime Minister Boris Johnson has said the "very, very tough" package of sanctions is "ready to go" should Russia invade Ukraine.

"What we're doing is targeting particular Russian banks, Russian companies, and making sure that we take steps, take even more steps, to unseal the facade of Russian property holdings... whether in London or elsewhere," Mr Johnson said on Tuesday.

"Unpeel the facade of Russian ownership of companies. And also take steps to take Russian companies from raising capital on London financial markets."