Britain will lock Russia's Sberbank (SBER.MM) out of sterling clearing and slap sanctions on three other banks, Foreign Secretary Liz Truss said on Monday, adding there would be a full asset freeze on Russian lenders within days.
Truss said that Russian President Vladimir Putin had been confounded by the collective response from Western countries after Moscow invaded Ukraine, and Truss said she wanted to go further on sanctions.
The government also advised citizens against all travel to Russia and ordered its ports to ban any vessels that are Russian flagged as it increased pressure on Moscow.
"We will bring in a full asset freeze on all Russian banks in days, looking to coordinate with our allies," Truss told parliament.
"This same legislation will prevent the Russian state from raising debt here and it will isolate all Russian companies, that's over 3 million businesses, from accessing UK capital markets."
Truss said she was bringing forward legislation to prevent Russian banks clearing payments in sterling, which would be applied to Sberbank when it came into force.
She also said full asset freezes would be imposed on Russia's VEB development, Sovcombank and Otkritiye.
Britain said it now advised against travel to Russia, citing a lack of available flight options to return to the UK after Britain and the European Union shut its airspace to Russian planes, prompting Russia to take similar action in retaliation.
Transport minister Grant Shapps on Monday also said that he had asked British ports "not to provide access to any Russian flagged, registered, owned, controlled, chartered or operated vessels."
"Further detailed sanctions against Russian shipping are being developed and further details will be shared very shortly," Shapps said in a letter to the ports.