The Kremlin vowed to retaliate last night after David Miliband, the Foreign Secretary, expelled four Russian diplomats from London because of Moscow’s failure to extradite the chief suspect in the murder of Alexander Litvinenko.

In a statement to the Commons, Mr Miliband took the boldest foreign policy decision of the new Government when he announced a series of measures against the Kremlin.

“The heinous crime of murder does require justice,” Mr Miliband said. “This response is proportional and it is clear at whom it is aimed.”

The four diplomats were not named, but they were thought to be senior officials with close ties to the security services. As part of the punitive action, the Foreign and Commonwealth Office will also take steps to tighten visa requirements for Russian officials visiting Britain, but not ordinary Russian visitors.

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Multimedia

• Full video of interview with Marina Litvinenko

BACKGROUND

• Lies and the spies: I must have justice

• Shadowy ex-KGB major takes cover

• Of course the Russians did it. They’re the experts

• The Litvinenko File

• Litvinenko was told that he was marked for death

Related Links

• Comment: Britain picks a fight it cannot win

• The Price of Murder

Moscow responded angrily to the British measures. Russia’s Foreign Ministry gave warning that Britain faced “the most serious consequences” for expelling its diplomats. “Officials in London have to realise that all provocative acts planned by the British authorities will not go unanswered and cannot help entailing the most serious consequences for Russian-UK relations in general,” said Mikhail Kamynin, a Foreign Ministry spokesman.

Mr Miliband told the Commons that the Government was forced to act because Moscow had failed to respond to Mr Litvinenko’s “horrifying and lingering” death from the deadly radioactive isotope polonium-210 in November last year. The Crown Prosecution Service named Andrei Lugovoy, a former Russian intelligence officer, as the main suspect in the murder, but Russia rejected a request last week for his extradition.

Gordon Brown, the Prime Minister, backed his Foreign Secretary last night, saying he “had no apologies for the action we have taken” in expelling the diplomats.

Mr Lugovoy insisted that he was the victim of a British conspiracy and rejected the allegations made against him as “brazen lies”. But Marina Litvinenko, Alexander’s widow, praised the British Government for its action. “It makes me proud to be a UK citizen because I can see that my strong faith in the British authorities was well founded,” she said.

Russia linked Britain’s demand for Mr Lugovoy’s extradition to the refusal by Britain to hand over Boris Berezovsky, the exiled billionaire, and Akhmed Zakayev, the Chechen envoy. Both men are wanted in Russia but have been granted political asylum by British courts.

“It seems to us that London’s position is immoral, given this background,” Mr Kamynin said. He added that Sergei Lavrov, the Russian Foreign Minister, had expressed this view in a telephone conversation with Mr Miliband. The Kremlin is seeking to take the moral high ground, accusing Britain of trying to force Russia to break its constitution.

But Mr Brown said: “I hope it’s understood in other parts of the world that we are not prepared to allow a situation of lawlessness to develop in London as a result of a failure to act.”

Sharing a platform in Berlin with Angela Merkel, Chancellor of Germany, he said people would understand that when a prosecuting authority made it clear what was in the interests of justice and when there was no co-operation, “then action has to be taken”.

Russia has a number of ways to hit back. At a minimum it is likely to expel British diplomats from Moscow, but it could also choose to harm British commercial interests and to withdraw co-operation on foreign policy issues, such as Iran.

Andrei Kokoshin, a parliamentary deputy for the ruling United Russia party, which supports President Putin, predicted that Britain’s economic interests would suffer “great harm”.

British companies invested £2.7 billion in Russia last year, making Britain the largest foreign investor. Russia received £1.5 billion in direct British investment in the first three months of this year, almost nine times more than the $364 million (£179 million) invested by US companies. Bilateral trade has grown to more than £10 billion a year and has been rising at an annual rate of about 20 per cent.

Investment boom

— Between 2000 and 2005 bilateral trade between Britain and Russia trebled from £2.759 billion to £8.473 billion

— Last year set a record for Russian exports to Britain, which is now the fifth-largest importer of Russian goods in the EU. In the same period, Britain was the EU’s fifth-largest exporter to Russia

— Foreign companies have invested heavily in Russia’s fuel and energy sectors. In June 2006, total investment by BP and Shell was valued at more than £8 billion. Both have since been forced to relinquish control of major projects to Russian giant Gazprom

— Gazprom supplies a quarter of Europe’s gas and oil. Britain imports 10 per cent of its gas, but only a fraction comes from Russia

— Although Britain is still the world’s fourth-largest producer of natural gas, North Sea fields are dwindling. It is thought that by 2020 Britain will need to import 50 per cent of its gas; Gazprom aims to supply 20 per cent by 2015

Sources: www.rbcc.com; UK Trade and Investment; www.gas-guide.org; www.oilandgas.org.uk; www.fco.gov.uk; The Bank Information Centre;Times database

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