A hitman sent to Britain to kill Boris Berezovsky was arrested by British security services as he planned the murder and then deported, it was confirmed tonight.

The gunman was spotted as he entered the country through Heathrow airport and placed on 24-hour surveillance after intelligence was received about the plot to kill the exiled Russian tycoon at the Hilton Hotel on London’s Park Lane.

Police had already warned Mr Berezovsky that it was not safe for him in this country and he had gone abroad a week before.

Scotland Yard tonight confirmed that the killer had been held on June 21 and then handed over to the immigration services on June 23 after having had his visa revoked. He was then deported and told not to return to the UK for at least ten years.

Today, Mr Berezovsky said that he had been tipped off several months ago by friends in Russia that a hitman was being sent to kill him, but did not really take it seriously.

It was only when Scotland Yard advised him to leave the country that he became concerned.

The assassin is said to have tried to lure Mr Berezovsky, a harsh critic of Russian president Vladimir Putin, to a room at the Hilton Hotel, near to his offices, where he planned to kill him.

Tonight, a Scotland Yard spokesman said: "We can confirm that a man was arrested on June 21, and released into the custody of the immigration services on June 23."

At a press conference today Mr Berezovsky said that Scotland Yard told him three weeks ago that it was not safe for him to remain in Britain.

"I was advised by the police to leave the country if I could. I went overseas for a week and then the police informed me that I could return.

"I have been asked by the police not to go into detail about the assassination attempt and therefore I will not do so."

But even before this friends from Russia who have connections to the FSB had warned him about the plot.

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