Ecuador's president said Thursday his government would take its time in deciding whether to grant asylum to Julian Assange as the WikiLeaks founder spent a second night at its embassy in London.

The 40-year-old Australian sparked a stand-off with British police after he turned up in the embassy on Tuesday and asked for asylum in a dramatic bid to avoid extradition to Sweden over allegations of rape and sexual assault.

Scotland Yard say the founder of the whistle-blowing website has breached his bail conditions and is now subject to arrest.

Ecuador's deputy foreign minister Marco Albuja said that President Rafael Correa would give his instructions within 24 hours, but Correa later indicated a longer timeframe was possible.

"He (Assange) presented his reasons. We are going to verify them... We will take the time necessary," Correa said, adding that it would be done "with absolute seriousness and absolute responsibility."

The leftist leader, who has often been at odds with Washington, said his government was studying Assange's claim that he could be extradited from Sweden to the United States on political grounds and possibly sentenced to death.

"Ecuador is a country which defends the right to life. We have to see whether there is a threat to Julian Assange's life," Correa said on the sidelines of the Rio+20 summit on sustainable development.

One British policeman stood guard on Thursday outside Ecuador's embassy, which is opposite the famed Harrods department in the upscale Knighstbridge area of London, an AFP photographer said.

Scotland Yard said early on Thursday that there had been no new developments overnight.

Britain's supreme court last week threw out Assange's application to reopen his appeal against extradition to Sweden after a marathon legal battle.

He has until June 28 to lodge an appeal at the European Court of Human Rights in Strasbourg, after which the extradition process can begin.

The asylum bid is the most dramatic twist yet in a case dating back to December 2010, when Assange was first detained in London on a European arrest warrant.

Anna Alban, the Ecuadorian ambassador, said in a statement on Wednesday that she had held "cordial and constructive" talks about the asylum request with Britain's Foreign Office.

"I also emphasised to the UK government that it was not the intention of the Ecuadorian government to interfere with the processes of either the UK or Swedish governments," she added.

The embassy said Assange would remain in the building under the protection of the Ecuadorian government while his application is considered.

Police said that by spending the night there, Assange had breached conditions to stay at his bail address between 10:00 pm and 8:00 am and "he is now subject to arrest under the Bail Act for breach of these conditions".

Britain's Foreign Office said however that because Assange was still on diplomatic territory he was "beyond the reach of the police".

The Sydney Morning Herald, citing WikiLeaks insiders, said Assange's decision to seek asylum was triggered by a letter from Australia's Attorney General Nicola Roxon, which he took as a "declaration of abandonment".

In the letter to one of Assange's legal representatives Roxon made it clear that Canberra would not seek to involve itself in any international exchanges about his future.

WikiLeaks enraged Washington by releasing a flood of classified US information about the wars in Iraq and Afghanistan, as well as more than 250,000 classified US diplomatic cables that embarrassed a slew of governments.