A few days after the British government requested the extradition of Andrei Lugovoi on suspicion of killing Alexander Litvinenko, the former KGB officer poisoned with polonium in London last year, Britain’s most wanted man spent a leisurely afternoon with friends and family at one of Moscow’s most exclusive social events. Sipping white wine in a VIP box overlooking Moscow’s racetrack as photographers took shots of him, Lugovoi placed bets and jumped up cheering when his nine-year-old son, Yegor, won £50.

Lugovoi appeared equally relaxed six weeks later when relations between Britain and Russia plunged to their lowest depths since the end of the cold war over Moscow’s blunt refusal to hand him over: the country’s constitution bars its citizens from being extradited.

And shortly after, as Britain expelled four Russian diplomats in protest and the Kremlin responded by kicking out four Brits, Lugovoi holidayed in luxury on the Black Sea. Since he became Britain’s most wanted man, his life, in short, has been one of endless VIP events, appearances on talk shows, and celebrity.

In a further snub to the British government, Lugovoi is standing for parliament in next Sunday’s elections as No 2 to Vladimir Zhirinovsky, the controversial leader of the ultranationalist Liberal Democratic party of Russia (LDPR). If elected, Lugovoi, who so far is not under investigation in Russia, would gain immunity from prosecution at home. The party may not win enough votes to stay in parliament, but polls show that his candidacy gave it a boost. Few may believe his vehement claims of innocence in Britain, but in Russia many will vote for him.

Over the past 10 months I have spent much time with Lugovoi and Dimitry Kovtun, a childhood friend who was with him in London when he last met Litvinenko, on November 1, 2006, the day the former KGB officer was poisoned. The meetings with him have been intriguing, lavish and occasionally bizarre: at one dinner in a Moscow restaurant, drinking from a £180 bottle of red wine and puffing from a Cuban cigar, Lugovoi denied any involvement in the murder and argued that he is the victim of a conspiracy hatched by Russia’s enemies and British intelligence. On a hunting trip in a remote forest close to the Volga river, I watched the two men drink vodka and sing sentimental communist-era songs around a camp fire. And at a party to celebrate Lugovoi’s 41st birthday, one guest presented him with a 1937 heavy machinegun mounted on wheels; another gave him a walking stick encrusted with precious stones and gold, which concealed a dagger in its handle.

Lugovoi invited me backstage during the LDPR party conference at which he launched his political career. He also took me in his chauffeur-driven BMW to a compound outside Moscow to watch him fire from a gun as bodyguards from his security company trained in the background.

He answered hundreds of questions about his KGB past, his current business and his alleged involvement in Litvinenko’s death. He never appeared to be off guard, and only once became agitated when I challenged his claims that he had nothing to do with Litvinenko’s poisoning. Nor did he make a secret of why he granted me access: “I wanted you to see me for what I am and make your own conclusions. Could I really have killed in cold blood then behave so calmly? I wanted you to watch how I behave, not only when I wear a tie but also when I sit by a fire and drink vodka. I have a very firm position: I’m innocent. I had nothing to do with it.”

Spending time with Lugovoi has been a journey that confounded my expectations. I suspected him, then believed his denials, only to later become even more confused, all while coming to like him, despite all my mistrust.

I have also watched him change. Apparently genuinely bewildered when his name was first linked to Litvinenko’s poisoning, only a few days before the former KGB officer died a slow and agonising death last November, Lugovoi has since become increasingly bullish and self-confident, if not cocky. He once asked if I could procure as a memento a copy of a British daily that ran his photograph on its front page.

The full truth about who ordered Litvinenko’s death or what role Lugovoi played in his murder, if any, is unlikely to be revealed. But in the story of a former KGB bodyguard-turned-businessman-turned-suspected killer-turned celebrity, there are echoes of the narrative of modern Russia.

Lugovoi’s world view, once enthusiastic about all things western, now increasingly distrusting and hostile, reflects those of millions of Russians. Similarly, his bullishness is indicative of Russia’s growing assertiveness, as it seeks to regain some of the influence it lost with the collapse of the Soviet Union. A millionaire businessman who is shadowed by bodyguards, he is also representative of a wealthy new elite born from the ashes of communism, which, as Lugovoi put it, “will be ruling Russia in the next 20 years”.

How is it possible, many will ask, that a man accused of the world’s first-known assassination involving a radioactive substance can have a political future? “Who is Lugovoi to the potential Zhirinovsky voter?” said Vladimir Pozner, one of Russia’s most respected political commentators. “If you believe he did murder Litvinenko, you say, ‘Good, Litvinenko was a traitor who should have been murdered, and this guy’s a hero.’ If you don’t believe he killed him, you say, ‘He is persecuted by people who hate us, the West, so he’s a hero.’ It’s a win-win situation.

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