WikiLeaks founder Julian Assange is making "wild assertions" about the United States in an attempt to divert public attention from justice he faces in Sweden, the US Department of State said.

"[Assange's] issue with the Government of the United Kingdom has to do with whether he's going to face justice in Sweden for something that has nothing to do with WikiLeaks. It has to do with charges of sexual misconduct," US State Department's spokeswoman Victoria Nuland told a daily press briefing, as cited by RIA Novosti.

In his first public appearance in two months on Sunday, which was from the balcony of the Embassy of Ecuador in London, Assange called on the United States to stop persecuting WikiLeaks staffers and website's supporters around the world.

"So 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," Nuland added.

Assange has been holed up in Ecuador's embassy in London for two months as he fights extradition to Sweden on sex crime charges, which he denies. Last Thursday Assange was granted asylum in Ecuador but he still faces arrest the minute he steps out of the embassy building.

The world's most famous whistleblower is suspected of sexual assault against two women that allegedly took place in August 2010. He claims the sex was consensual and the accusations against him are politically motivated.

WikiLeaks' publication of US diplomatic cables on November 29, 2010, containing forthright comments from US diplomats about foreign leaders and events, caused an internet sensation and enraged US officials. WikiLeaks previously published tens of thousands of documents about the actions of American soldiers in Iraq and Afghanistan.