Ministers are considering emergency legislation to push through sanctions on Russian oligarchs linked to President Putin.
Government sources have told Sky News that experts are looking at whether current laws could be tweaked or new ones brought in to speed up the process, which has stalled over recent days.
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Although a spokesman for the prime minister stated today that legal processes are not responsible for a lack of action on individual sanctions, others have warned that tougher rules on how the government freezes assets mean the system has ground to a halt while legal hurdles are cleared.
Foreign Secretary Liz Truss told MPs last week that her department has a “hit-list” of wealthy Russians whose property, businesses and cash could be frozen if sanctions were signed off.
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But there is understood to be frustration at the speed of the process and suggestions that the government is allowing wealthy Russians the opportunity to move their cash.
In a briefing to journalists on Wednesday, UK government officials said sanctions need to be legally watertight to avoid them being unpicked at a later date – a process which can be costly.
Ministers have repeatedly pointed to the broad range of sanctions introduced by the government, including on major banks and other industries.
But there have been calls for sanctions to be introduced against high-profile individuals such as Roman Abramovich, the owner of Chelsea.
Mr Abramovich, who has denied having links with the Russian president, announced on Wednesday that he would be putting the west London club up for sale.
The “net proceeds” of the transaction will go to benefit victims of the war in Ukraine, he said in a statement.
A government source told Sky News that sanctions have to be well-targeted, but acknowledged that the process does need to move faster.
They added that ministers have not ruled out using parliamentary privilege to list a group of individuals who the UK wants to sanction, if other options fail.
It comes amid calls from Labour for the government to amend a separate piece of legislation, due before the House of Commons on Monday.
The Economic Crime Bill aims to make it easier for the government to understand where assets of overseas-nationals are held in the UK, but it has been criticised after it emerged that those who already own property in the UK will be given an 18-month grace-period to register their property.
Critics believe this will allow oligarchs to move their money out of the country or to make it harder to track.
Labour has proposed reducing the 18-month period to 28 days, something Boris Johnson said he was open to discussing.
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Sky News understands that experts are working to reduce the time, after a “drafting issue” was blamed for the excessive grace-period.
There are legal concerns about forcing foreign nationals who do not have anything to do with President Putin to register their assets and businesses and fears that such a tough new law could deter investment in the UK.
The time is likely to be reduced before the bill is voted on by MPs, although sources were not clear on how long the period would be.