UNITED NATIONS (AFP) - President George W. Bush has had to grit his teeth and put up with one of the most anti-American UN General Assemblies in recent years.

The annual meeting of world leaders is never easy for the global superpower. But speeches by Venezuelan President Hugo Chavez and Iran's Mahmoud Ahmadinejad, attacking Bush personally as "the devil", or his policies as "hegemonist", left a sulphurous atmosphere around the UN headquarters.

Even a supposed ally, Pakistan's President Pervez Musharraf, let fire on the sidelines by daring to disagree with Bush over who whether U.S. forces would be allowed to grab Osama bin Laden if the Al-Qaeda leader were found on Pakistani territory.

"It has been one of the most shrill displays of anti-Americanism in recent years," said one ambassador from the pro-U.S. camp on the UN Security Council to describe the performances by Ahaminejad and particularly Chavez.

The Venezuelan president mercilessly lambasted the U.S. leader with a speech 24 hours after Bush defended his attempts to bring democracy and liberty to the Middle East from the General Assembly stage. "Yesterday the devil came here," said Chavez.

"And it still smells of sulphur today."

His act in crossing himself and looking up to pray to the almighty, brought some undiplomatic laughter and applause. Chavez, whose country is a key U.S. oil supplier, followed it up Thursday on tour of New York's Harlem district. While offering to send more heating oil to poor families in the United States, Chavez called Bush "an alcoholic" and "a sick man."

Bolivia's left wing president, Evo Morales, also made a colorful anti-U.S. statement by holding up a coca leaf, which is banned in the United States but a staple in Bolivia, to back his protest against the U.S. handling of its war on drugs.

Ahmadinejad was less personal but no less brutal in his judgment of Bush's administration. In a scathing attack on the United States and Britain, Ahmadinejad slammed the "hegemonic powers" who imposed "their exclusionist policies on international decision-making mechanisms, including the Security Council." While the United States leads the diplomatic charge for sanctions against Iran because of its nuclear program, the Tehran leader highlighted that some of his opponents "have abused nuclear technology for non-peaceful ends" and "some even have a bleak record of using them against humanity."

The U.S. administration put a brave face on the attacks, hinting that it used to being in the firing line.

"People will judge for themselves how seriously to take the comments and the people who make them," said State Department spokesman Sean McCormack.

British Foreign Secretary Margaret Becket said that Chavez and Ahmadinejad would only have a limited influence.

"It is fairly clear that they are both people who wish to allege that the U.S. and UK are in some way acting as a particular force and are in some way causing problems to the rest of the international community," Beckett told reporters.

She preferred to highlight how 38 countries have joined the United States and Britain in Afghanistan and how "many, many nation states" were helping to rebuild" Iraq.

"That is not how the UN works," she said of the Chavez shock tactics.

But what Chavez and Ahmadinejad said out loud about U.S. policies and the need for reform of the United Nations, some other leaders uttered more quietly in their speeches to the assembly.

Brazil's President Luiz Inacio Lula da Silva spoke just before Bush on Tuesday.

Lula highlighted the hundreds of billions of dollars spent on the U.S. military occupation of Iraq and declared "with much less we can change the sad reality of a great part of the world population" fighting hunger and disease. Lula said the handling of Middle East conflicts, especially the Lebanon crisis, had exposed the "dangerous erosion of the UN's credibility and effectiveness."

"Some leaders appear to think that Mr. Bush is already a lame duck and that hunting season is open," said one diplomat in New York.