Alistair Darling, the Secretary of State for Trade and Industry, has complained to the Kremlin over its treatment of British companies, arguing that the way in which Shell was strong-armed out of a majority stake in the Sakhalin-2 oil and gas venture was unacceptable.
Mr Darling, in Moscow to cement Britain's role as the largest foreign investor in Russia, warned that UK companies would be reluctant to invest in Russia in future unless they know that the contracts they sign are going to be honoured.
"I made it very clear that British companies coming here need to have legal certainty, and need to know where they stand. Once rules are fixed they should stay that way," Mr Darling told reporters after meeting three Russian ministers.
Mr Darling's words are likely to be carefully listened to in Kremlin circles. Last year, Britain ploughed $5.5bn (£2.8bn) into the Russian economy in the first nine months of the year.
London has also become the listing centre of choice for Russian companies; last year Russian firms raised more than $15bn there. If the relationship is to continue to flourish, Mr Darling made it clear he expected better treatment for UK firms.
He signalled he did not want to see a repeat of what he called "the Sakhalin episode", in which Shell was strong-armed into selling its controlling stake in the world's largest offshore oil and gas project.
"The episode caused concerns... and after what happened in Sakhalin people are apprehensive," he said. He called for greater restraint in future. "It would be far better if these matters were settled in accordance with established laws."