The former Russian spy who died last week from radiation poisoning named a senior Kremlin agent as the man he believed responsible for targeting him.

Alexander Litvinenko, who died after mysteriously absorbing polonium-210, a rare and highly toxic radioactive material, said in his last full interview from hospital that he knew he was an “active case” for Russian intelligence.

Hundreds of Brits call hotline to ask about polonium-210 poisoning.

He named the agent in charge of monitoring him as “Viktor Kirov”. A man called Anatoly V. Kirov worked at the Russian embassy in London, where he was listed as a diplomat, until late last year.

He is believed to have left the diplomatic service in October 2005 and returned to Russia. But Litvinenko claimed just days before he died that Kirov was an intelligence agent who continued to target him.

Poison case detectives to fly to Moscow.

Yesterday, antiterrorist squad police requested that The Sunday Times hand over a tape of the interview in which Litvinenko named Kirov. Detectives from Scotland Yard’s Counter Terrorist Command SO15 are on standby, if required, to travel to Moscow to interview people involved in the case.

Litvinenko’s claim — though he did not accuse Kirov of any direct involvement in his poisoning — will reinforce suspicions that he was killed by an assassin with links to state intelligence. Experts believe that an individual or organization with access to a sophisticated nuclear facility could have obtained polonium-210.

Cobra, the British government’s emergency committee, met yesterday to discuss the unprecedented case and was chaired by Tony McNulty, the counter-terrorism minister. Polonium radiation was first found at Litvinenko’s home in north London last Thursday.

“High doses” were later found at several sites in London and ministers fear public alarm about contamination. Police have discovered that several rooms at a hotel visited by Litvinenko were contaminated.

Litvinenko’s wife Marina has already been tested for polonium contamination. “She is in the clear,” said a Whitehall source. At least 100 other people are to be tested, and NHS Direct has been inundated with calls from members of the public who fear they may be contaminated.

The investigation into Litvinenko’s death threatens to have serious diplomatic repercussions. Kim Howells, the Foreign Office minister, said: “What everybody seems to forget is that this guy was a naturalized British citizen and they [Cobra] take a very dim view of British citizens being murdered on British streets by foreign nationals.”

The Tory party will be asking for a Commons statement from the government about the affair tomorrow.

A senior Foreign Office source said it had no indication that Moscow was behind the plot: “We don’t have any evidence to finger point.” However, British officials have formally asked the Russian embassy to provide assistance.

Yesterday an aide to President Vladimir Putin reacted strongly to suggestions of Russian involvement. “We don’t know who killed Litvinenko, but one thing is for sure, it was not the Russian state,” he said. “We’ve got nothing to hide.”

The aide implied Litvinenko’s death was part of a conspiracy by enemies of Putin who had sacrificed one of their own to discredit the Russian president. “If you ask the question who has the most to gain from all this, the answer can only be [Boris] Berezovsky, a man who by his own admission is out on a campaign to discredit Putin and the Kremlin,” he said.

The billionaire Berezovsky fled Russia in 2000 and lives in Britain. He knew Litvinenko well and supported him financially. Berezovsky declined to comment yesterday, but friends said it was absurd to accuse him of any involvement in Litvinenko’s death.

Last week The Sunday Times obtained a home telephone number for Kirov from a former agent of the FSB, the Russian secret intelligence service. The number was confirmed by a second source. However, the man who answered the telephone denied being Kirov or ever having been in London.

The SVR, Russia’s foreign intelligence service, declined to say whether Kirov is or has been an agent. The Russian foreign ministry denied any role in a plot to kill Litvinenko.

Assistant Commissioner Andy Hayman, the head of specialist operations at Scotland Yard, has told ministers it is too early to conclude that Litvinenko was murdered. The police have kept an open mind, and still consider it possible Litvinenko poisoned himself by accident or deliberately.

However, an unnamed official from the International Atomic Energy Agency, the United Nations nuclear watchdog, was quoted as saying Litvinenko’s death bore the hallmarks of an “organized operation” by an intelligence agency because of the expertise needed to obtain and administer polonium-210.

Speaking from his hospital bed eight days before he died, Litvinenko said: “I know that Russian intelligence are monitoring me. I know I am an active case. I know that the officer in the Russian station here who is in charge of monitoring me is Mr. Viktor Kirov. Until he left, [he] was consul in the Russian embassy . . . I know that he is part of the spy trade and among other things, was monitoring my movements.”

Litvinenko is believed to have previously complained to British police that Kirov had been harassing him at home at night.

During his interview in hospital, Litvinenko said recent changes to the law in Russia had given the state more power to attack critics: “The Russian parliament passes a law in the middle of this year which allows the government, allows the president, to pursue and attack terrorists and extremists all over the world. So it’s now legal.”

Litvinenko also said he might be suffering from radiation, rather than other, poisoning as originally feared. Doctors were unable to identify the deadly substance until a few hours before his death on Thursday night.

Geiger counters that doctors initially used to test Litvinenko for radiation failed to detect it and polonium-210 was found only when further tests were conducted on his urine. Yesterday the Health Protection Agency (HPA) said only special modeling had revealed the polonium. “In many other countries it would never have been detected, which may be why it was used.”

Traces of polonium have been found at Litvinenko’s home; at Itsu, the London restaurant where he met Mario Scaramella, an Italian contact; at the Millennium hotel in Piccadilly where he saw a former FSB agent; and at the hospitals where he was treated. Scotland Yard said last night that arrangements were being made for the Piccadilly restaurant to be decontaminated.

Police are studying documents purporting to identify a potential assassin and five “enemies of Russia”, including Litvinenko, who should be eliminated. Those named were Scaramella, a security consultant who supplied the documents to Litvinenko on November 1, the day he was poisoned; Berezovsky; an Italian senator called Paolo Guzzanti; and the dissident Vladimir Bukovsky.

The documents Scaramella showed Litvinenko came from a KGB defector who is living under the protection of the French security services.