Julian Assange has told his lawyer it's a "victory" that Swedish prosecutors have performed an about-face and finally agreed to interview him in London regarding allegations he sexually assaulted two women in 2010.
Prosecutors had previously refused to consider quizzing the 43-year-old inside the Ecuadorean embassy where he's been holed up for almost three years.
Assange's Swedish lawyer Per Samuelson woke the WikiLeaks founder on Friday morning to deliver the news via telephone.
"This is a victory for me, this is what I've been asking for for more than four years," Assange said according to Mr Samuelson.
"Finally it's coming and it's a good opportunity to give my version of what happened to the prosecutor and clear my name."
But Mr Samuelson told AAP that Assange, who denies the allegations, was also irritated it had taken the prosecutor so long to change her mind.
"She has wasted over two years of my life," the 43-year-old reportedly said.
It's not yet known when the interview will take place.
Mr Samuelson will travel to London on Saturday to discuss the case with Assange.
The UK and Ecuadorean authorities need to officially approve the questioning although that should be a formality.
Britain's Foreign Office on Friday said "we stand ready to assist the Swedish prosecutor as required".
Ecuador's Foreign Minister Ricardo Patino said "from the first day we have offered to let (prosecutors) question him".
The Court of Appeal in Stockholm late last year refused Assange's request to set aside his 2010 detention order.
But in the process the court noted the investigation had ground to a halt and stated "the failure of the prosecutors to examine alternative avenues is not in line with their obligation".
Friday's move came after Assange appealed again to Sweden's Supreme Court which earlier this week asked the prosecutor-general to issue an opinion.
Mr Samuelson suspects Anders Perklev then ordered Assange be interviewed in London.
Prosecutor Marianne Ny on Friday said she was now prepared for Assange to be quizzed in the embassy because the statute of limitations on some of the alleged crimes would become effective in August.
"My view has always been that to perform an interview with him ... in London would lower the quality of the interview and he would need to be present in Sweden in any case should there be a trial," Ms Ny said in a statement.
"(But) now that time is of the essence I have viewed it therefore necessary to accept such deficiencies to the investigation."
Swedish Prosecution Authority spokeswoman Karin Rosander said she didn't know when the interview would take place.
"We cannot make any guesses because it depends on circumstances that are outside our reach," Ms Rosander said.
"We need to get a go-ahead from the British and Ecuadorean authorities."
After losing a UK legal battle against extradition Assange entered Ecuador's diplomatic mission in June 2012 and was granted political asylum two months later.
The Australian fears if he goes to Sweden he'll be extradited to the United States and charged over WikiLeaks' release of classified documents.
WikiLeaks spokesman Kristinn Hrafnsson on Friday said the Swedish offer didn't mean Assange would be able to walk out of the embassy anytime soon.
"We have to worry about the ongoing criminal investigation in the US," he said.
