Julian Assange has been arrested by British police and was carried from the Ecuadorean embassy after his South American hosts abruptly revoked his seven-year asylum, paving the way for his extradition to the United States.

Key points: Assange was arrested for "failing to surrender to the court" in 2012, police said

Assange was arrested for "failing to surrender to the court" in 2012, police said He has been taken into custody and will appear in court as soon as possible

He has been taken into custody and will appear in court as soon as possible Police were invited into the embassy after the Ecuadorian Government withdrew asylum

The US alleged the Australian-born founder of WikiLeaks engaged in a 2010 conspiracy with Chelsea Manning, who served seven years in military prison for leaking classified data, and charged him with conspiracy to commit computer intrusion with a maximum penalty of five years' prison.

"In March 2010, Assange engaged in a conspiracy with Chelsea Manning, a former intelligence analyst in the US Army, to assist Manning in cracking a password stored on US Department of Defence computers connected to the Secret Internet Protocol Network (SIPRNet), a US government network used for classified documents and communications," the US statement read.

An agitated, frail-looking Assange with white hair and a white beard was carried head first out of the embassy shortly after 9:00am (local time) by at least seven men to a waiting police van.

Julian Assange is arrested by UK police. ( Ruptly )

Police said they arrested Assange after being invited into the embassy following the Ecuadorean Government's withdrawal of asylum.

"The whole House will welcome the news this morning that the Metropolitan Police have arrested Julian Assange, arrested for breach of bail after nearly seven years in the Ecuadorean embassy," Prime Minister Theresa May told House of Commons MPs to cheers and cries of "Hear, hear!".

Australian Minister for Foreign Affairs Marise Payne said that Assange "will continue to receive the usual consular support from the Australian Government".

"I am confident, as the United Kingdom Foreign Secretary Jeremy Hunt publicly confirmed in July 2018, that Assange will receive due process in the legal proceedings he faces in the United Kingdom," she said.

"As the matter is the subject of law enforcement and legal proceedings we will not provide ongoing comment."

She added that consular officials "would seek" to visit Assange at his place of detention.

Free speech hero or security risk?

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 2 minutes 12 seconds 2 m 12 s Who is Julian Assange and what is WikiLeaks?

The arrests, after nearly seven years holed up in a few cramped rooms at the embassy, mark one of the most peculiar turns in a tumultuous life that has transformed the programmer into a rebel wanted by the US.

Assange's supporters said Ecuador had betrayed him at the behest of Washington, that the termination of his asylum was illegal and that they feared he would ultimately end up on trial in the US.

To some, Assange is a hero for exposing what supporters cast as abuse of power by modern states and for championing free speech.

But to others, he is a dangerous rebel who has undermined US security.

Assange gave a thumbs up in handcuffs as he was taken from a police station, and he later appeared in Westminster Magistrates' Court.

WikiLeaks angered Washington by publishing hundreds of thousands of secret US diplomatic cables that laid bare often highly critical US appraisals of world leaders, from Russian President Vladimir Putin to members of the Saudi royal family.

Assange made international headlines in early 2010 when WikiLeaks published a classified US military video showing a 2007 attack by Apache helicopters in Baghdad that killed a dozen people, including two Reuters news staff.

A police van parked outside the Ecuadorian Embassy in London, after WikiLeaks founder Julian Assange was arrested by officers. ( AP: Rebecca Brown )

Ecuadorian romance goes sour

Assange took refuge in Ecuador's London embassy in 2012 to avoid being extradited to Sweden, where authorities wanted to question him as part of a sexual assault investigation.

That probe was later dropped, but Assange has long feared he could be extradited to face charges in the United States, where federal prosecutors are investigating WikiLeaks.

Friends of Assange said the solitude he had experienced in the embassy had hurt him most.

Loading

"It was a miserable existence and I could see it was a strain on him, but a strain he managed rather well," said Vaughan Smith, a friend who visited him.

"The thing that was most difficult for Julian was the solitude.

"He was very tough, but the last year in particular was very difficult. He was constantly being surveilled and spied upon. There was no privacy for him."

WikiLeaks said Ecuador had illegally terminated his political asylum in violation of international law.

"Assange's critics may cheer, but this is a dark moment for press freedom," said Edward Snowden, a former US National Security Agency contractor who fled to Moscow after revealing massive US intelligence gathering.

Assange's relationship with his hosts collapsed after Ecuador accused him of leaking information about President Lenin Moreno's personal life.

A poster is attached to a barrier across from the Ecuadorian Embassy in London, after WikiLeaks founder Julian Assange was arrested. ( AP: Matt Dunham )

Mr Moreno said the nation withdrew Assange's asylum status "after his repeated violations to international conventions and daily-life protocols".

Mr Moreno said he had requested that the United Kingdom guarantee the WikiLeaks founder "would not be extradited to a country where he could face the death penalty or torture".

"The patience of Ecuador has reached its limit on the behaviour of Mr Assange," Mr Moreno said.

Ecuador's Foreign Minister José Valencia also confirmed the country had stripped Assange of his Ecuadorian citizenship.

Expulsion from embassy not a surprise

Kristinn Hrafnsson, editor in chief of WikiLeaks, right, warned awaiting global media about the threats to journalism. ( Reuters: Henry Nicholls )

WikiLeaks last week foreshadowed his impending removal from the country's London embassy, and recently alleged that Ecuador was culpable in a sophisticated spying operation on Assange.

WikiLeaks claimed Mr Moreno's remarks were in retribution for it having reported on corruption accusations against him, although he denied wrongdoing.

Loading

Relations between Assange and Ecuador had grown increasingly prickly as the years have dragged on, and the Australian had faced increasing pressure to leave the embassy in recent months.

Mr Moreno last year cut off Assange's access to the internet, ordering him to stick to a new set of house rules, including avoiding contentious political issues, cleaning his bathroom and looking after his cat if he wanted the internet reconnected.

Speaking outside London's Westminster Magistrates' Court, WikiLeaks editor Kristinn Hrafnsson told reporters it would be "horrible" if the Assange's extradition was carried through.

"The UK Government must declare that they will never, ever extradite a journalist for doing journalism," he said.

"If this goes forward, no journalist anywhere in the world will be safe from extradition to the US, from doing his job or even to another country."

Australian Minister for Foreign Affairs Marise Payne said Assange "will continue to receive the usual consular support from the Australian Government".

"I am confident, as the United Kingdom Foreign Secretary Jeremy Hunt publicly confirmed in July 2018, that Assange will receive due process in the legal proceedings he faces in the United Kingdom," she said.

"As the matter is the subject of law enforcement and legal proceedings we will not provide ongoing comment."

She added that consular officials "would seek" to visit Assange at his place of detention.

On social media, actress Pamela Anderson — who has previously detailed her friendship with Assange and lashed out at Prime Minister Scott Morrison for "trivialising" his situation — wrote that she was "in shock".

"He looks very bad. How could you Equador [sic]?" she tweeted.

"Because he exposed you."

ABC/wires