Assange is on a flight home to Australia after spending more than five years in London's high-security Belmarsh prison fighting extradition to the United States for revealing US state secrets.

"I am very pleased that on this occasion, this has been a successful outcome that I believe overwhelmingly Australians did want to see," Prime Minister Anthony Albanese told parliament in Canberra.

"They will have different views about the engagement and the activities of Mr Assange but they will be pleased that the saga has been brought to an end and that he will be able to reunite with his family."

Under the plea agreement, the 52-year-old Australian citizen pleaded guilty to a single charge of conspiracy to obtain and disseminate defense information and was sentenced to time already served.

The legal drama unfolded in a courtroom in the Northern Mariana Islands, a Pacific US territory.

Albanese said the resolution of Assange's case was the result of "careful, patient and determined work -- work I am very proud of".

"I have said repeatedly that there was nothing to be gained by his continued incarceration, and I am pleased that he is on his way home to Australia," he said.

"Regardless of your views about his activities, and they will be varied, Mr Assange's case has dragged on for too long."

The prime minister confirmed that the Australian ambassador to the United States, Kevin Rudd, and Australia's high commissioner to the UK, Stephen Smith, were both accompanying Assange on his flight home.

Assange, who in 2010 published hundreds of thousands of confidential US documents on the whistleblowing website, walked free after a plea deal with the United States ended years of legal drama for the WikiLeaks founder.

He was released this week from a high-security British prison.

The 52-year-old traveled to the Northern Mariana Islands, a Pacific US territory, to plead guilty to a single count of conspiracy to obtain and disseminate national defense information.

He was sentenced Wednesday to five years and two months in prison -- but credited for the same amount of time he spent behind bars in Britain while fighting extradition to the United States.

"You will be able to walk out of this courtroom a free man," the judge told Assange, adding she hoped the deal would restore some "peace" to him after his incarceration.

Assange has become a hero to free speech campaigners and a villain to those who thought he had endangered US security and intelligence sources.

"Working as a journalist, I encouraged my source to provide material that was said to be classified," Assange, dressed in a black suit with a brown tie and his hair slicked back, told the court.

He did not address the media as he left the building, and his plane took off shortly after for Canberra, where he will be reunited with his family.

WikiLeaks said on X that it would hold a press conference in the Australian capital at 9:15 pm (1115 GMT) on Wednesday, though it did not elaborate on whether Assange would be present.

Assange's lawyer Jen Robinson told reporters it was a "historic day" that "brings to an end 14 years of legal battles."

"It also brings to an end a case which has been recognised as the greatest threat to the First Amendment in the 21st century," she said.

The Northern Mariana Islands was chosen for the hearing because of Assange's unwillingness to go to the continental United States and because of its proximity to Australia.

The United Nations also welcomed Assange's release, saying the case had raised human rights concerns.

The US Justice Department said after the hearing that Assange was banned from returning to the United States without permission.

US authorities had wanted to put Assange on trial for divulging military secrets about the wars in Iraq and Afghanistan.

He was indicted by a US federal grand jury in 2019 on 18 counts stemming from WikiLeaks' publication of a trove of national security documents.

The material included video showing civilians being killed by fire from a US helicopter gunship in Iraq in 2007. The victims included a photographer and a driver from Reuters.

Assange was held in London's Belmarsh prison from 2019 after spending seven years in Ecuador's embassy in the UK capital to avoid extradition to Sweden, where he faced accusations of sexual assault that were eventually dropped.