The UK plans new legislation this week to broaden sanctions against Russian businesses and people close to President Vladimir Putin if an invasion of Ukraine goes ahead.
The US, EU and Britain have repeatedly warned Mr Putin against attacking Ukraine after Russia massed about 100,000 troops near the border with its former Soviet neighbour.
London became the centre for a vast outflow of money from former Soviet republics after the 1991 collapse of the Soviet Union and opponents of Mr Putin have repeatedly called on the West to get tough on Russian money.
“We are very clear that if Russia takes further action against the Ukraine, then we will further tighten the sanctions regime targeting those businesses and people with the closest links to the Kremlin,” Treasury minister Simon Clarke told Sky News on Monday.
The US Senate is also close to finalising sanctions that could lead to Russian banks being hit and extra military aid being made available to Ukraine, for which it can pay later. Russia is in a position to ride out the immediate impact of sanctions, with a record high of $630bn in foreign assets held by the country's central bank in December, according to website Trading Economics.
The UK Foreign Secretary Liz Truss said on Sunday that the current British sanctions regime only allowed companies with a direct involvement in destabilising Ukraine to be targeted.
Under the new plans, the programmed would be widened to include Russian financial institutions, energy companies and oligarchs close to the Kremlin.
“Any company of interest to the Kremlin and the regime in Russia would be able to be targeted, so there will be nowhere to hide for Putin's oligarchs, for Russian companies involved in propping up the Russian state,” said the foreign secretary, who is due to visit Ukraine and Russia in the next two weeks.
She told Sky News that “nothing is off the table” including the ability to seize property in London.
But the Centre for American Progress, a US think tank, said last week that Britain would face a challenge uprooting wealthy Russians with Kremlin links from London given close ties “between Russian money and the United Kingdom’s ruling Conservative party, the press, and its real estate and financial industry".
The former head of intelligence agency MI6, John Sawers, said he believed that a mixture of sanctions and military support to Ukrainian forces could stop Russia from invading.
He said the practicalities of invading and holding Ukraine would be a consideration for Russian military planners and they could be deterred from invading with the other measures.
“We know that from watching the American forces in Iraq in 2003 a major, sophisticated army can march to the capital and depose a government,” he told the BBC.
“The really difficult thing is to hold that territory. Ukraine is the size of Germany and France put together and 100,000 Russian troops could march to Kiev but can they hold the country?”
