Venezuelan President Hugo Chavez told Prime Minister Tony Blair to "go right to hell" last night Mr Blair said Venezuela should abide by the principles of democracy.
Mr Chavez, who recently compared US President George W Bush to Adolf Hitler, accused Mr Blair of bowing to Washington's interests and being "shameless" and "immoral."
"Stay in your place, Mr Blair, you are not one that has the morality to criticise anyone," Mr Chavez said during a speech. "Venezuela is a free nation. Do you believe we're still in times of imperialism and colonialism?"
"Go right to hell, Mr Blair," Mr Chavez said, using local slang that is more vulgar.
Shifting his aim after a recent flare-up in tensions with the United States, Mr Chavez called the premier the principal ally of "Hitler Danger Bush Hitler", referring to his favourite nickname for Mr Bush, "Mr. Danger."
During a parliamentary session yesterday, Mr Blair called on Venezuela to respect the rules of the international community and said he would like to see Cuba, a close ally of Venezuela, function as a true democracy.
"I think the most important thing is that those countries in South America and North America realise they have much in common, much to gain from each other and ... in particular through the principles of democracy," Mr Blair said.
Chavez characterised Blair's remarks as an effort by London to fall in line with Washington's increasingly harsh criticism of Venezuela, whose latest spat with the United States flared up last week when Mr Chavez accused its main oil buyer of spying.
Mr Chavez noted the statement came shortly after Mr Bush called for increased funding for a US radio station broadcasting pro-American messages in Latin America.
The nation's ambassador to Venezuela was in Miami yesterday and unavailable for comment.
"There's nothing to add to what the prime minister has already said," an embassy spokesman said.
Since Mr Chavez - a former army officer and leader of a failed 1992 coup - was elected in 1998, ties with the United States have steadily deteriorated, although Venezuela still supplies some 15 per cent of US oil imports.
Mr Chavez says his "revolution for the poor" is an alternative to US capitalist policies in Latin America. He has sought energy and trade deals within the region and annoyed the United States by allying himself with countries like Cuba and Iran.