Law360, London (November 10, 2022, 12:53 PM GMT) -- The British government said on Thursday that it has frozen a total of £18.4 billion ($21 billion) in Russian assets after the country invaded Ukraine, establishing what it called the most stringent financial sanctions package in history.

HM Treasury said that figures released by its internal Office of Financial Sanctions Implementation reveal the full scale of the measures. The total amount of assets frozen and reported to the OFSI was approximately £6 billion more than reported across all the other U.K. sanctions packages.

The government said that, with its international allies, it has sanctioned more than 1,200 individuals and over 120 entities. It has also frozen the assets of 19 Russian banks with global assets of £940 billion since Vladimir Putin launched the invasion in February, OFSI's annual review has revealed.

Andrew Griffith, Conservative MP and Economic Secretary to the Treasury, said the U.K. remains united with its allies to oppose "Russia's barbaric and unprovoked invasion. We have imposed the most severe sanctions ever on Russia, and it is crippling their war machine."

Griffith added that the government has committed to doubling OFSI's headcount to maintain pressure on Moscow. The OFSI report says the office has doubled the number of its staff from 45 at the beginning of the year and expects to expand to around 100 by the end of 2022.

"Our message is clear: we will not allow Putin to succeed in this brutal war," Griffith added.

Anne-Marie Trevelyan, minister at the Foreign Office, also warned of further action. "We will continue to ramp up our sanctions to exert maximum economic pressure on the Russian regime until Ukraine prevail," Trevelyan said.

Governments across the globe have launched a range of economic strategies to hamper Moscow's resources. The Treasury cited figures that predict Russia's GDP will fall by up to 6.2% in 2022 compared with forecasts from before the invasion.

Almost $30 billion in Russian assets has been blocked or frozen, according to figures published in June by a global alliance of governments known as the Russian Elites, Proxies and Oligarchs Task Force.

The OFSI has levied a series of sanctions against Putin's regime and Russian businessmen. The European Union has also imposed six packages of sanctions on Russia and those connected to the Kremlin since its full invasion of Ukraine began.

And the U.S Department of the Treasury's Office of Foreign Assets Control ramped up its sanctions in September by cutting off more than 300 individuals, including 278 members of Russia's legislature, from U.S. financial institutions.

--Additional reporting by Najiyya Budaly and Jennifer Doherty. Editing by Ed Harris.

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