Forget Miliband vs Miliband. The most hotly contested leadership vote of the season will take place next week in the small Siberian city of Khanty-Mansiysk. Delegates from more than 100 countries will choose between two Russian candidates after a lengthy campaign filled with acrimony and allegations of corruption.

The prize at stake is the top position in world chess – president of the World Chess Federation (Fide) – and the contest is being fought between former chess grandmaster Anatoly Karpov, and the current president, the eccentric Kirsan Ilyumzhinov, a millionaire and the leader of Kalmykia, an oil-rich Buddhist region on the Caspian coast.

Mr Ilyumzhinov is no normal politician. He counts among his friends the American actor Chuck Norris and the late Saddam Hussein, has made chess lessons mandatory for all schoolchildren during his two decades in power in Kalmykia, and has built the largest Buddhist temple in Europe. Oh, and he also believes that chess was brought to Earth by aliens, and that if not enough people take up the game, the aliens might destroy our planet. Author of an autobiography with chapter headings that include "Without me the people are incomplete" and "It only takes two weeks to have a man killed", Mr Ilyumzhinov has combined his political job with running Fide since 1995.

Mr Ilyumzhinov met with The Independent in Moscow to put forward his platform for the Fide elections, and to share his views on life. First, though, he wanted to talk about his latest grand plan. Perturbed by protests over the "Ground Zero Mosque", he has written to New York Mayor Michael Bloomberg, offering $10m (£6.5m) to build a World Chess Centre on the site instead. Religion, he says, is supposed to unite people, but of late it has been dividing them.

His plan is to build a 24-storey tower on the site of the planned mosque in the shape of a king chess piece. "Chess is a human activity which brings together the human brain and the competitive spirit. But it's a competition without blood. There are 64 squares, and there is no blood," says Mr Ilyumzhinov. He emphasises this in his letter to Mr Bloomberg, in which he expresses the "dream" that in the future, the only battles between East and West will be "over a chessboard".

Inside the chess centre, he says, there will be a mosque, a church, a synagogue and a Buddhist temple. The king's crown will be an observatory where children can look at the stars. A chess school will give free lessons, and there will be a powerful bank of computers that will run intercontinental online chess competitions. "However much people play football now, in 100 or 200 years, people will have forgotten about it. Chess will remain forever," he says. "For example, we will say that today, at 3pm, Europe will play with America," says Mr Ilyumzhinov, getting animated at the idea. "And whoever wins will be able to say they are the cleverest continent."

He says that he will not use his considerable personal wealth to fund the project, but expects huge interest from wealthy friends, including Russian billionaires Alexander Melnichenko and Roman Abramovich. A source close to Mr Abramovich de

nied that the Chelsea owner had any interest in the project.

Then Mr Ilyumzhinov gets into the theme he is infamous for: extraterrestrials. He has claimed on many occasions that in 1997 he was taken by aliens to a spaceship, where he chatted with them before returning to Earth. You do realise, he asks, that chess is a "cosmic game"? Excavations have shown that chess was played with similar rules, in various continents, centuries ago, he says, adding: "There was no internet before, so how did it get across the world? It means that it was brought from somewhere."

He also insists that there is "some kind of code" in chess, evidence for which he finds in the fact that there are 64 squares on the chessboard and 64 codons in human DNA. He then explains why he believes sweetcorn was brought to Earth by a different civilisation. "I'm not ill. I'm psychologically normal," he says. "I didn't hide it [the contact with aliens] even though I knew that people would laugh at me and say I was crazy. Maybe it was a form of self-sacrifice."

Indeed, his claims have brought much derision, as well as prompting one Russian parliamentarian to call for an investigation into whether Mr Ilyumzhinov gave away any state secrets during his encounter. But for all the harm it has done his image, he has somehow managed to remain a successful public figure. This, after all, is a man who has run one of Russia's regions with Kremlin support for two decades. Mr Ilyumzhinov has been accused of corruption on many occasions, and one of his top aides was jailed for the murder of an opposition journalist in 1998. The Kalmyk opposition were sure that when his term expired in 2005, he would finally be replaced. Instead, Mr Putin flew to Kalmykia and reappointed him for another five-year term.

But when his term runs out next month, he will have to give up the trappings of power. And it seems that the Kremlin is determined to ensure its man gets a consolation prize, and continues to run Fide. In a vote in May, the Russian Chess Federation backed the chess legend Mr Karpov as its candidate and it appeared to be game over for Mr Ilyumzhinov. In response, armed security men were sent to the headquarters of the Russian Chess Federation by the Kremlin's points man for chess, Arkady Dvorkovich, who in his day job is one of President Dmitry Medvedev's most powerful advisers.

The nomination of Mr Karpov was overturned, and Mr Ilyumzhinov was promoted instead. Mr Dvorkovich also wrote to all the other Fide members' states and asked them not to back Mr Karpov. "I have won Russia at least 16 world championships," Mr Karpov told the New York Times. "With all due respect to Dvorkovich, who is an assistant to the President on specific economic programs, why does he think he knows chess better than I do?"

Mr Karpov secured nominations from other countries, so the election is set for a showdown between the two Russians. But why is the Kremlin backing such an odd candidate? The answer perhaps lies in Mr Karpov's running mate – Garry Kasparov.

Former enemies both across the chessboard and in real life, an unlikely alliance has formed between Mr Karpov, who has always been seen as a man of the system, and Mr Kasparov, who runs a radical and marginalised opposition political party. Mr Karpov and Mr Kasparov accuse Mr Ilyumzhinov of turning world chess into a farce, and several leading chess players have spoken out against his candidacy. There have been allegations that Mr Ilyumzhinov's campaign has pressured smaller countries with threats and promises of funding.

Mr Ilyumzhinov denies all this. "It's all because Kasparov needs a political forum, and he can use the chess arena as a platform," he claims. "Karpov was a world champion 30 years ago. Now he's just a pensioner sitting at home."

His main goal, if he is re-elected, is to increase the number of chess players in the world from 600 million to a billion. And he has serious reasons for wanting this to happen. "Above us, they are looking at us, and maybe they will get tired of us, and suddenly..." he tails off, making dramatic gestures of destruction. "How can we save ourselves from them? Only though intellect, concentration and spiritual energy. If a billion people are in these chess centres, playing chess, the world will have positive energy."

Other alien encounters...

Robbie Williams

During a sabbatical from his pop career, the ex-Take That star took up UFOlogy, attending a conference on the subject in Nevada. "This is possibly the most important thing ever to happen to the planet," he said.

Jimmy Carter

Before he became US President, Jimmy Carter saw a UFO. "It was just a peculiar-looking light," he said. "None of us could understand what it was." When campaigning for the White House, he promised he would take sightings seriously.

Dan Aykroyd

The star of Ghostbusters, who is also "Hollywood consultant" for a popular UFO website, said in 2007 that aliens are "coming and going like taxis" because "we are the centre of the universe". He added: "They're visiting because this is the planet that produced Picasso."

General Douglas MacArthur