The US has accused WikiLeaks founder Julian Assange of making "wild assertions" about an alleged US vendetta against him to deflect attention from rape allegations he faces in Sweden.
State Department spokeswoman Victoria Nuland dismissed Mr Assange's latest public statement, which he delivered on Sunday from the balcony of the Ecuadorean Embassy in London where he has sought refuge from arrest.
She said Mr Assange's current legal problems stemmed from allegations of sexual misconduct and were unrelated to the WikiLeaks case.
"He is making all kinds of wild assertions about us," Ms Nuland told a news briefing.
"He is clearly trying to deflect attention away from the real issue, which is whether he's going to face justice in Sweden, which is the immediate issue.
"So that case has nothing to do with us. It's a matter between the UK, Sweden, and now Ecuador has inserted itself."
Mr Assange demanded on Sunday that US President Barack Obama end what he called a "witch-hunt" against his whistle-blowing website.
He was speaking from the Ecuadorean mission to avoid being detained by British police who want to extradite him to Sweden for questioning about rape allegations by two women.
Ecuador's socialist president Rafael Correa, a vocal critic of US foreign policy, granted the former computer hacker political asylum last week, deepening a diplomatic stand-off with Britain and Sweden.
Ms Nuland referred questions about any potential future US legal action against Mr Assange to the Justice Department but said he would not face "persecution" in the US.
She also accused Ecuador of seeking to stir up trouble at the Organization of American States, where supporters of Mr Correa's government have called for a foreign ministers' meeting on the Assange affair.
"We don't think that's an appropriate forum," Ms Nuland said. "We have very important business that we do in the OAS that has to do with the strength and health and democracy in the region, and this is, frankly, a sideshow."
Mr Assange incensed the US and its allies by using his WikiLeaks website to leak hundreds of thousands of secret US diplomatic and military cables in 2010, disclosures that often embarrassed Washington.
His supporters claim that he will ultimately be extradited to the US if he goes to face charges in Sweden and that he could face the death penalty there for the leaking of sensitive government material.
Yesterday, hundreds of Ecuadoreans marched in support of their government's decision to grant asylum to Mr Assange in a saga that could help President Correa win re-election.
Ecuador is outraged at Britain for threatening to enter its embassy in London.
