His latest sensation, Borat Sagdiyev, started life as a fringe character in the hit Da Ali G Show, mercilessly lampooning Kazakhstan as a backward haven of Jew-haters where woman are kept in cages and killing dogs is the national sport.

Unsurprisingly, the country's leaders were miffed. But rather than letting the satire wane, they fuelled the frenzy with a reaction that even Dubya might not regard as proportionate. First there were threats of legal action, to which Borat responded: 'I have no connection with Mr Cohen and fully support the government's decision to sue this Jew.'

Two western PR firms were then hired before colour adverts appeared in prestigious western newspapers, promoting Kazakhstan as modern and outward-looking. But the estimated US$400,000 cost of those campaigns pales in comparison to the roughly US$50 million spent on a sweeping new movie called Nomad.

The historical epic, which is the most expensive movie ever made in Kazakhstan, tells the story of a handsome 18th century warrior who unites Kazakh tribes in their struggle for freedom from Mongol invaders. Displaying a touch of hubris, Mr Nazarbayev appears at the beginning and end of a film he hopes will enhance the nation's reputation abroad.

As one of the production team, Rustam Ibragimbekov, declared: 'The world knows about cowboys, gladiators and samurai, but not nomads. Maybe he should have added Borat to his 'world knows about' list. In his improbably titled new film, Borat: Cultural Learnings of America For Make Benefit Glorious Nation of Kazakhstan, the sexist and racist diatribes extend to politically incorrect levels previously unreached.

During a quest to meet and marry Pamela Anderson, Borat refers to his sister as 'number four prostitute in whole of Kazakhstan' and shows the local tradition of the 'running of the Jew', a variation on Pamplona's annual bull run.

The set-ups will come as no surprise to fans of Da Ali G Show, who have become used to Borat's shock tactics in recent years. When he convinced organisers of a rodeo in Salem, Virginia, that he was shooting a serious documentary, Borat infuriated the crowd by stating: 'I hope you kill every man, woman and child in Iraq, down to the lizards, and may George W. Bush drink the blood of every man, woman and child in Iraq.' After mangling the words of the American national anthem, he was escorted from the arena for his own safety. In Tuscon, Arizona, he asked the audience at a country music bar to clap and sing along with his song Throw the Jew Down the Well.

Although he has come under fire from Jewish and anti-racism groups, Cohen, who is himself a Jew, says the reaction to Borat's racist nature demonstrates how racism feeds on dumb conformity, as much as rabid bigotry.

Borat also takes potshots at celebrities. During his appearance at MTV's Europe Music Awards in November, he called Madonna a 'genuine transvestite'. 'He was very convincing,' said Borat. 'It was only his hands and teste satchels that gave it away.' While Madonna took Borat's joke in good humour, it was a skit mocking Mr Nazarbayev that prompted a somewhat paranoid-sounding Foreign Ministry spokesman, Yerzhan Ashykbayev, to suggest Cohen was acting on behalf of 'someone's political order'.

That Borat's origins are nothing more than a comic device seems to have escaped the leaders of the former Soviet republic, who fear his antics are making their great nation a global laughing stock. You would have thought that Borat's response to the threat of legal action would have offered the bureaucrats some clues. 'Kazakhstan is as civilised as any other country in the world,' he howled in mangled English that has become his trademark. 'Women can now travel inside of bus. Homosexuals no longer have to wear blue hats. And age of consent has been raised to eight years old.'

Borat's family history is even more ridiculous. He presents himself as one of four children. His sister, Natalya, is a prostitute and one of his brothers, Bilo, is mentally ill and has a son with excessive body hair. Borat is a father of three children aged under 13, and 17 grandchildren. He has two wives, a mistress, a girlfriend, and another woman 'I have to pay for'. His first wife was tragically killed by a hunter who mistook her for a bear. His ideal woman is blonde with a toned body and no family history of 'retardation'. Plough experience is essential. In fact, it is the virtually universal ignorance of Kazakhstan in the west that allows Borat to get away with making up everything he says, and land hits on the real targets of his humour, usually unwitting Americans.

Last week battle lines were drawn once again as Mr Nazarbayev prepared for his visit to Washington. The Kazakh government produced special inserts in The New York Times and International Herald Tribune and bought air time on US TV channels to get the positive message across. But once again it was Borat who won the day. He brandished a copy of the Times insert outside the Kazakh embassy in Washington, declaring the content as 'disgusting fabrications' perpetrated by 'evil nitwits' from neighbouring Uzbekistan, who he threatened to attack 'with our catapults'.

'As we all know, [they] are very nosy people with a bone in the middle of their brain,' he said. Chased by 50 journalists, Borat then walked to the White House and rang the buzzer. 'I like to give Premier Bush an invitation to see screening my film,' he told a secret service agent. 'Do you have an appointment?' was the answer. 'Eh, not so much,' he replied before conveying the invitation for the Friday night screening, with cocktails and conversation about US-Kazakh relations to follow at Hooters.