WikiLeaks founder Julian Assange is set to be cleared of three sexual assault allegations made in Sweden within days, as a five-year statute of limitations against the charges expires.

Three of the charges of sexual molestation involving two women he met during a visit to Sweden five years ago will expire on August 13 and August 18.

The statute of limitations on a fourth and more serious allegation of rape is not set to expire for another five years.

Never charged

Assange, who has been holed up at the Ecuadorian Embassy in London for more than three years, has never been charged with any offence and has denied all of the allegations.

His lawyer, Thomas Olsson, told Swedish Television last week that it was "lamentable that it's taken such a long time to wind up this case" and called on Swedish prosecutors to close the investigation.

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However, he said it was unlikely that the closing of the case itself would be enough to prompt Assange to leave the embassy, where he has sought asylum since June 2012, as he remained concerned over being extradited to the US to face charges over WikiLeaks' publication of classified US military and diplomatic documents.

"The reason he is at the embassy is his concern over being extradited to the US and prosecuted there because of the very serious accusations the US made about WikiLeaks publications and because of personal threats made by people in public office," Olsson said.

"So long as that threat remains - and it's a threat of global scope - he can't leave the embassy."

On Wednesday the Financial Times reported that Ecuador had agreed to hold talks with Sweden about questioning Assange, a move which could end a years-long stand-off.

Swedish officials said Ecuador had wanted Sweden to sign a bilateral agreement on judicial cooperation regarding Assange's case before allowing Swedish prosecutors to question him. Sweden described the demand as unreasonable.

Assange's lawyer Olsson said Assange's lawyers had for several years requested prosecutors to come and interrogate Assange "but had not had a reply".

"What people forget is that Julian Assange voluntarily attended the first interrogation and answered the questions he was asked," Olsson said.

"Then the investigation was closed and a new prosecutor arrived on the scene to open it again."

Bradley Manning, a US army soldier, in 2013 was sentenced in a military court to a maximum term of 35 years' jail for passing on thousands of classified military documents to WikiLeaks for publication.