President Hugo Chavez blamed the expulsion of a Venezuelan diplomat from the United States on "counter-revolutionaries" in the latest flare-up between Washington and its most prominent foe in Latin America.
President Barack Obama's government ordered out Venezuela's consul general to Miami last weekend after the TV network Univision aired allegations she had in the past discussed cyber-attacks on the United States with Iranian and Cuban diplomats.
But Chavez, giving his government's first response to the case late on Monday, said that the move against Livia Acosta Noguera was "arbitrary and unjustified."
Venezuelan intelligence had known it was coming and protectively kept her in Caracas since December, he added during a news conference with Iranian President Mahmoud Ahmadinejad.
"She is a dignified professional, attacked, slandered and demonized by that group of extremists in the United States and now by Barack Obama's government," he said.
Venezuela's government says exiled nationals - who are based in the US state of Florida and are bitterly opposed to the socialist Chavez government - are influencing US policy towards Caracas.
"They are counter-revolutionaries, not all of them, but a little group ... from the ultra-right," he said, promising a formal response to the expulsion shortly.
"It's another demonstration of the ridiculous empire's arrogance."
The latest spat in a long line of diplomatic disputes between Venezuela and the United States during Chavez's 13 years in power came at a sensitive time during the Iranian leader's visit to the region.
Washington, which is turning the screw on Iran over its nuclear policy, has urged nations to cool ties with Tehran. But Chavez, and fellow leftist governments from Nicaragua, Cuba and Ecuador also hosting Ahmadinejad this week, have scoffed at the US call and are making a show of welcoming him.
Despite their political differences and past threats of disruption, OPEC-member Venezuela remains one of the United States' main oil suppliers, creating a mutual economic dependence that appears to trump ideological differences.
The US-based Council on Hemispheric Affairs think tank suggested that the Obama administration, with a presidential election looming in November, was largely ignoring Latin America except for issues that might play well to domestic voters.
"Votes could be picked up from rightist exile groups coming from Cuba, Nicaragua, and Venezuela among other disaffected conservatives, who hold passionate thoughts on their personal political agendas," it said in a paper.
