New sanctions have been announced targeting Russia's central bank.
The moves come after the Central Bank of the Russian Federation (CBR) doubled its key interest rate following a 30 per cent slump in the rouble prompted by sanctions from the West.
Today (Monday) Prime Minister Boris Johnson and his Chancellor Rishi Sunak trumpeted further measures the UK, US and the European Union were taking to stop the Kremlin plundering foreign reserves to mitigate the effect of existing sanctions.
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The new measures ban anyone in the UK from doing any business involving the CBR, the Russian National Wealth Fund, and the Ministry of Finance of the Russian Federation, according to the Treasury.
Other Russian financial institutions are also being targeted while Russian companies are also being stopped from dealing in the money markets in the UK, it said.
A power adopted in the US to prevent designated Russian banks from accessing the banking system is being matched here, according to an official statement.

A new ban on the export to Russia of 'high end and critical technical equipment' in the electronics, telecommunications and aerospace sectors was also announced.
The original package of sanctions is said to target more than 100 companies and oligarchs at the heart of President Vladimir Putin’s regime, whose assets have been frozen and travel bans have been imposed.
The European Union, US, UK and allies yesterday agreed to exclude a number of Russian banks from Swift, an international payment system used by thousands of financial institutions.
Announcing the latest measures, Chancellor Rishi Sunak said: "These measures demonstrate our determination to apply severe economic sanctions in response to Russia’s invasion of Ukraine.

"We are announcing this action in rapid co-ordination with our US and European allies to move in lockstep once more with our international partners, to demonstrate our steadfast resolve in imposing the highest costs on Russia and to cut her off from the international financial system so long as this conflict persists."
Prime Minister Boris Johnson tweeted: "We have further isolated Russia from the international financial system this morning. Working with our partners, and the G7, we are determined to impose the most severe economic measures possible against President Putin for his abhorrent campaign against Ukraine.
"Putin must fail."