The outspoken Chavez littered his speech to the UN world summit with anti-US comments which were strongly applauded. The ally of Cuba's President Fidel Castro followed this up with a press conference at which he accused the US administration of supporting terrorism.

Tensions have been mounting between the United States and Venezuela for months.

President George W. Bush's government has accused Chavez of becoming a destabilizing influence in Latin America. Chavez has in turn threatened to cut off his country's valuable oil supplies to the United States.

Their dispute has been spiced up by a call from US conservative evangelist, Pat Robertson, for the United States to assassinate Chavez, a comment he later apologised for.

Chavez told the UN General Assembly that the United States was "a country that does not respect the resolutions of this assembly."

To loud applause he took up the call of Latin American revolutionary Simon Bolivar for the UN headquarters to be moved to "an international city" in the southern hemisphere.

"It is time to think about an international city," he said, just before being told that his speech had gone beyond the allotted 15 minutes for each of the 170 heads of state and government leaders at the summit.

Chavez took the opportunity to fire a new assault at the US leader, claiming that Bush had been given 20 minutes.

At a press conference after his speech, Chavez said that the United States was a "terrorist state" because of its actions in Iraq, Robertson's assassination call and for harboring Luis Posada Carriles, who is wanted for the bombing of a Cuban airliner.

"It is a terrorist state. It is a government that violates all rules and behaves shamelessly," he said.

"The United States is the champion of double standards. The United States' government defends terrorism. They talk of the fight against the terrorism, but they commit terrorism, state terrorism," said Chavez.

The Venezuelan president said the United States had used napalm in Iraq and protects Posada Carriles, who is being held in the United States on immigration charges.

The Venezuelan leader arrived in New York on Thursday morning having kept in doubt whether he would attend the summit at all.

Chavez charged Tuesday that the United States had denied visas to his security and medical teams. He also complained that his presidential jet had been ordered to an airport far from the UN building.

Stepping up the diplomatic hostilities, as Chavez arrived, the US administration released a report saying that Venezuela had "failed demonstrably" to meet its counternarcotics obligations over the past year.