WikiLeaks founder Julian Assange says he will "soon" leave Ecuador's embassy in London, where he has been holed up for two years to avoid extradition.

Police have been stationed at the compound since Mr Assange requested political asylum from Ecuador in June 2012, ready to arrest him if he sets foot outside.

The 43-year-old Australian, who is reportedly suffering from heart and lung problems, gave a press conference on Monday evening amid speculation he was set to hand himself over.

Asked about the reports, Mr Assange said: "I can confirm that I am leaving the embassy soon, but perhaps not for the reasons that the Murdoch press and Sky News are saying at the moment."

He gave no further details.

Asked about his health, Mr Assange said anyone would be affected by spending two years in a building with no outside areas or direct sunlight.

Sorry, this video has expired Timeline: Assange's time in embassy

Swedish prosecutors want to question Mr Assange over sexual assault allegations made by two female former WikiLeaks volunteers.

Mr Assange denies the allegations and has been fighting a legal battle against extradition since his arrest in Britain in 2010.

"Through all that time, nearly four years, I have not been charged with an offence ... and there has been no public indictment," said Mr Assange, flanked by Ecuador's foreign minister Ricardo Patino.

"How can it be that such a situation in Europe arises where a person is held and their freedom of movement is restricted and they are kept from their family while a foreign government, the United States, builds an ever larger case against that person and their organisation?"

'Two years is simply too long'

Mr Assange fears Sweden could in turn extradite him to the United States to be tried for one of the largest leaks of classified information in US history.

"First of all, I have not been charged with an offence here in the United Kingdom or in Sweden at any time," he said.

"Secondly, the basis under which my asylum was granted is the ongoing US investigation into me and WikiLeaks."

Mr Patino did not mention a plan for Mr Assange to leave the embassy but called for the governments involved in his case to take action.

"The situation must come to an end - two years is simply too long," he said.

Sorry, this video has expired WikiLeaks Party spokesman Gerry Georgatos discusses Julian Assange's fate

"We continue to offer him our protection ... we continue to be ready to talk with the British government and the Swedish government to find a solution to this serious breach of Julian Assange's human rights."

WikiLeaks spokesman Gerry Georgatos says he expects Mr Assange will be a free man when he leaves the embassy.

"If it means that he needs to walk out and create a confrontation and be escorted to Ecuador - where he's got asylum, where he's got that right to asylum which is his basic human right - this is what will actually unfold," he said.

"It can't be that he will remain in there for six, seven, eight, nine, 10 years. Things have come to a head."

A spokesperson for the Department of Foreign Affairs and Trade says Australian officials "have previously provided consular assistance to Mr Assange, but he has not requested any such assistance for some time".

"If Mr Assange seeks consular assistance, the Government will extend an appropriate level of service according to the circumstances, but that assistance will not extend to intervening in UK or Swedish legal processes," the spokesperson said.