Chess legend Garry Kasparov talks to the BBC News website about Putin, politics and the game of kings.
After 20 years of dominating the chess world, establishing recognition as perhaps the greatest in the centuries-long history of the game, Kasparov has a very different opponent in his sights.
To Kasparov, Russian President Vladimir Putin's regime is tantamount to "fascism", dismantling Russian democracy with the support of a supine West, which is interested only in stability in the East.
Kasparov is widely regarded as history's greatest chess player
In London for work on a new book and promotional events, the world number one said allowing Moscow to host the G8 summit in 2006 would be the equivalent of Nazi Germany being allowed to host the Olympics in 1936.
"[It is vital] to make sure there is no G7 meeting in Moscow in 2006. It will be like the Berlin Olympics in 1936, it will be the equivalent of Munich 1938, integrating Putin's Russia.
"The democracies are conceding to a brutal dictator. He has abolished the nature of democratic institutions. He will go further."
The West must stop its overt and tacit support for Mr Putin, Kasparov said.
"What is required from the West is a simple message: 'Leave us alone.'
"Don't support Putin. It is not about giving support to us, but Putin's main support comes from Western leaders.
"President Bush is not shy about calling this KGB colonel his friend."
Putin is rapidly destroying democracy, according to Kasparov
Kasparov was born in the Azerbaijan capital Baku in 1963 to a father of Jewish descent and an Armenian mother.
Ever since his victory over Anatoly Karpov in 1985 to become world champion Kasparov has been portrayed as an outsider who took on the Soviet establishment.
Kasparov helped set up Committee 2008, a group dedicated to bringing down Mr Putin and stopping the constitution being changed so that he can run for a third term, in January last year.
He takes heart from what has happened in Ukraine, and believes Mr Putin will have to leave office, perhaps even before his second term comes to an end in 2008.
"There could be popular unrest. The stability [of Russia] exists only in the mind of Bush and Blair.
"It lives through high oil prices and censorship."
Liberal opponents in Russia say Mr Putin's control of the media and incidents like the recent forced sale of oil firm Yukos' assets make democracy impossible.
Kasparov said the Yukos sale was "the greatest robbery of the 21st Century".
But supporters of Mr Putin point to the 71% share of the vote he took in last year's presidential election, and his high approval ratings.
The president himself has said he is upholding democracy and fighting corruption, and that Russia has standards that compare to anywhere in the West.
But monitors from the Organization for Security and Co-operation in Europe criticised the presidential election and earlier elections to the Duma.
Away from the political arena, Kasparov is facing a frustrating time in chess.
Instead of being in London, getting mobbed at a book signing at the Chess and Bridge shop on Euston Road, and working on a new book, Kasparov should have been preparing for a World Championship match with Uzbek star Rustam Kasimdzhanov.
But their match in Dubai, a prelude to a match with world champion Vladimir Kramnik, was cancelled by the governing body of chess, Fide, after financial guarantees by the promoters failed to be offered. Kasparov is not pleased.
Kasparov is in London writing and promoting his series My Great Predecessors
"Frustrating is a very soft word. It hurts me not only psychologically and chess-wise, but it is causing substantial material damage.
"It shows Fide has no respect for players and the professional elements of the game.
"It is too hypothetical to discuss anything unless I see the colour of the money."
While admitting his match performance must be good, Kasparov seems a little sceptical about his opponent's credentials.
"He is 25 in the world by rating and I think he belongs there."
And he is scathing about former protege Vladimir Kramnik's reign as world champion.
"I'm the number one player in the world, Kramnik is number four.
"He has failed to play the number one or the number two. He contributes to the mess as much as Fide does."
He admits: "I don't care. I no longer have the same passion for playing the world championship."
For the moment, he prefers to concentrate on his writing, including his popular history of the world champions.
It is testament to his status in the game that he has been able to entitle the books My Great Predecessors without risking sounding arrogant.
The fourth in the series, on the enigmatic American genius Bobby Fischer, currently facing extradition to the US from Japan on sanctions-busting charges, is already selling well.
But Kasparov will not offer an opinion on who is the greatest.
"Writing the books I had to walk in the shoes of these great personalities and look at the events through their eyes.
"I am setting out the information for readers to decide."