Sweden has withdrawn an arrest warrant for WikiLeaks founder Julian Assange, who had been wanted on suspicion of rape and molestation.

The National Prosecutor's Office said in a statement on its website that Chief Prosecutor Eva Finne had determined there were not enough grounds for the warrant.

A spokeswoman for the prosecutor's office said Mr Assange, whose whistle-blowing website last month published secret US military files on Afghanistan, was no longer wanted by Swedish authorities.

‘She (Finne) has come to the decision that he is no longer suspected of rape. All the charges concerning rape have been lifted,’ she told Reuters.

A police investigation will continue.

Earlier, Mr Assange, whose whereabouts were unclear, told WikiLeaks' Twitter page the charges were ‘without basis and their issue at this moment is deeply disturbing’.

He was in Sweden last week to discuss his work and defend his intent to publish further documents on the war in Afghanistan.

Mr Assange has close contacts in the Nordic country, which has some of the world's strictest laws on the protection of sources and where WikiLeaks also keeps many of its servers.

WikiLeaks wrote on Twitter that it had not been contacted by police.

‘We were warned to expect 'dirty tricks'. Now we have the first one,’ WikiLeaks, whose page has more than 100,000 followers, tweeted. It also provided a link to the right-leaning tabloid Expressen, which first published the allegations.

US officials said WikiLeaks' release of more than 70,000 documents detailing the war in Afghanistan was one of the biggest security breaches in US military history.