Julian Assange plans to walk out of Ecuador’s embassy a free man, avoiding arrest and extradition to Sweden to face questioning about sexual assault and rape allegations.

In an exclusive interview with Fairfax Media, Mr Assange said he anticipated legal reforms in Britain would facilitate a resolution of his circumstances and end the prospect of his extradition to Sweden.

The WikiLeaks publisher flummoxed the international media on Monday by telling reporters in London that he will “soon” be leaving his refuge in Ecuador’s London embassy, but not elaborating on how long “soon” might be or the circumstances in which he will end his diplomatic asylum.

“I can confirm I am leaving the Ecuadorian embassy soon,” Mr Assange said at a joint press conference with Ecuadorian Foreign Minister Ricardo Patino.

Mr Assange’s remarks were preceded by a flood of speculation by international media and on Twitter that health problems were about to force him to surrender to British police.

Mr Assange acknowledged that his health had “deteriorated” during two years of confinement in Ecuador's embassy, but said that his eventual departure would be “not for the reason you might think” - an apparent reference to media reports that he has developed a significant heart ailment.

In a subsequent interview with Fairfax Media, however, Mr Assange clarified his remarks by referring to what he described as “a range of important legal developments in the United Kingdom,” especially the British government’s decision to opt out of the European Arrest Warrant system under which Sweden sought his extradition to be questioned about sexual assault and rape allegations first raised in August 2010.

Mr Assange was granted political asylum by Ecuador in June 2012 on the grounds that he is at risk of extradition to the United States to face conspiracy or other charges arising from the leaking of hundreds of thousands of secret US military and diplomatic documents by US soldier Chelsea Manning.

British police are on guard outside the embassy 24 hours a day, waiting to arrest Mr Assange so he can be extradited to Sweden.

Mr Assange's lawyers have advised that his extradition to Sweden could facilitate his extradition to the US. The British and Swedish governments have declined to provide assurances that Mr Assange would not be extradited to the US. The Australian government has indicated that it will not make any representations on Mr Assange’s behalf.

At the joint press conference Mr Assange again called on the US government to end its ongoing investigation of WikiLeaks and himself.

Mr Patino said Mr Assange’s confinement had gone on too long.

“The situation must come to an end, two years is too long.  It is time to free Julian Assange, time to respect his human rights,” Mr Patino said.

Speaking to Fairfax Media, Mr Assange said he believed that British legal reform and debate in the British Parliament showed that "the mood is shifting, there is now an understanding that what I have been saying about the injustice of arrest and extradition without charge was right all along".

Mr Assange also noted that Mr Patino had indicated his intention to arrange an early meeting with his new British counterpart, Foreign Secretary Philip Hammond, to reopen discussions on Mr Assange’s circumstances.

Asked by Fairfax Media whether he expected to leave the embassy in months rather than years, Mr Assange said “there have been many significant developments that are likely to result in a much faster resolution.”

Mr Assange highlighted support he has received from human rights groups in Europe and the US and pointed out that Human Rights Watch had called on the US to stop its investigation of him.

Despite Mr Assange’s confinement in Ecuador’s embassy, WikiLeaks has continued to publish leaked documents including, over the past year, secret draft treaty texts from the controversial Trans-Pacific Partnership and Trade in Services Agreement negotiations, as well as a secret suppression order relating to references to south-east Asian politicians and others in a major criminal trial in Victoria’s Supreme Court.