Russia has drawn up a list of Americans who are banned from entering the country, in a tit-for-tat response to a US move to blacklist dozens of Russian officials accused of involvement in the death of the lawyer Sergei Magnitsky.
During Barack Obama's presidency, relations between Moscow and Washington have undergone a much-vaunted "reset", but the Magnitsky case is aggravating tension, with Moscow furious at what it sees as pressure and interference in its internal affairs.
Sergey Ryabkov, Russia's deputy foreign minister, told the respected daily Kommersant yesterday that Russia's retaliatory list would include "people who cause problems in Russian-American relations".
Another source in the foreign ministry told the paper that the list involved "people who took part in the cases against, for example, Viktor Bout and Konstantin Yaroshenko".
Mr Bout was extradited to the US from Thailand in November 2010 on suspicion of weapons trafficking, after being arrested when he allegedly offered to sell weapons to US agents posing as Colombian rebels. He has denied all the charges and says he is a legitimate businessman.
Mr Yaroshenko, a cargo pilot, was detained last year in Liberia and was convicted in April by an American court of attempting to smuggle drugs into the US via Latin America. Russia says that that the Americans essentially kidnapped Mr Yaroshenko and extradited him from a third country without their permission.
The exact names of the people on the Russian list have not been made public, and the popular Russian website Snob joked that it was possible that Nicholas Cage was among the people placed on the Russian blacklist. The Hollywood actor played a shady arms dealer loosely based on the character of Mr Bout in the 2005 film Lord of War.
The original American list contains officials from the interior ministry and prosecutor's office implicated in Mr Magnitsky's death. He died in a Moscow prison in 2009 after being charged with helping the investment fund Hermitage Capital evade taxes. He denied the charges, and his supporters say they were trumped up by corrupt officials trying to cover up an enormous tax fraud that the lawyer had uncovered.
William Browder, the founder and chief executive of Hermitage, has accused Russia of attempting to cover for those behind the alleged fraud, and said yesterday it was cynical to equate the cases of Mr Bout and Mr Yaroshenko with the Magnitsky case.
"Now that the US government is banning those torturers and murderers involved in the Magnitsky case from coming to the US, instead of prosecuting any of the key people involved, the Russians are retaliating by imposing their own sanctions on US officials prosecuting Russian arms dealers and drug smugglers," Mr Browder said.
Labour MP Chris Bryant told The Independent yesterday that he believes the Russian officials on the US blacklist should also be banned from the UK. "I have provided a list to the Home Office and strongly pushed that they should not allow any of these people visas to the UK," he said.