Officials say ministers have become increasingly frustrated by failure to agree terms with sanctioned Russian oligarch

Ministers are preparing to take Roman Abramovich to court in a final attempt to free up more than £2bn from the sale of Chelsea FC to spend as aid in Ukraine, the Guardian has learned.

Officials say ministers have become increasingly frustrated by the failure to reach an agreement with the sanctioned Russian oligarch about how the money should be spent, and are now ready to fight him in the courts.