Former Prime Minister Kevin Rudd was byJulian Assange's side as he touched down for his court appearance on Pacific island to formally end his 14-year legal battle against espionage charges.
The 52-year-old Assange arrived on Saipan, the capital of the Northern Mariana Islands, owned by the United States, at about 6.15am on Wednesday.
Assange had agreed on Tuesday to plead guilty to a single criminal count of conspiring to obtain and disclose classified US national defence documents, according to court filings.
Taking into account time served, Assange is expected to be immediately freed to return to Australia.
Assange is expected to land in Canberra just after 6.40pm AEST.
The WikiLeaks founder was joined in Saipan by Mr Rudd, Australia's ambassador to the US, who escorted Assange into the US District Court.
Both Assange and Mr Rudd appeared relaxed and smiled as they navigated their way through camera crews.
Assange had arrived by a private jet along with a legal team and Australia's ambassador to the UK Stephen Smith, ahead of Wednesday's hearing (Australian time).
Kevin Rudd was spotted by Julian Assange's side as he touched down for his court appearance on an island in the Pacific following a 14-year legal battle
Assange has been summoned to the third floor of the District Court to face one criminal count:conspiring to unlawfully obtain and disseminate classified information relating to the national defence of the United States, in violation of 18 USC, section 793(g).
Another court document states that US Justice Department officials 'anticipate that the defendant will plead guilty to the charge.'
Once the proceedings are over, Wikileaks and his family say Assange will be free to return to Australia, which could be as soon as Wednesday evening.
He'd spent five years in a maximum security prison in London's Belmarsh Prison, and seven years in asylum in theEcuadorian embassy in the UK.
For Assange it is a much better outcome than the initial prospect of being extradited to the US mainland to face charges and potential life imprisonment.
'It's a great victory for freedom of expression and also justice,' Greg Barns, SC, legal advisor to the Australian Assange Campaign, told AAP.
Assange and Mr Rudd are seen walking into the US District Court inthe Northern Mariana Islands in the Pacific
'Julian faced the prospect of over 170 years in a US jail if he'd been convicted of the charges for which the Americans were seeking to extradite him.'
Assange's Wikileaks publicly released a trove of classified military and diplomatic material which exposed information to the US was trying to keep secret, and was accused of thereby endangering military personnel and compromising operations.
Assange and his supporters insist he was doing nothing different to media organisations who expose confidential government material.
Alexander Downer, who was Australian High Commissioner to the UK while Assange was seeking asylum in the Ecuadorian embassy in London, said he doubted Australians would have sympathy for him.
'What he did was a criminal offence, and it was a terrible thing to do, morally as well, and endangering people's lives in that way,' he told the BBC.
Australia's government was placed in a dilemma by the case - whether to get the best outcome for Assange as a citizen, or to maintain strong defence ties with the US by allowing America to dictate his legal treatment.
Prime Minister Anthony Albanese had directly raised the issue with US President Joe Biden and a group of politicians from across Australia's political spectrum converged on Washington in September to lobby US decision-makers.
'Regardless of the views that people have about Mr Assange's activities, the case has dragged on for too long,' Mr Albanese said.
Assange's family are relieved at his release, with his father John Shipton praising the Australian government for its efforts to end the 'persecution' of his son.
The pair seemed relaxed as countless media crews waited outside the courthouse
'I am absolutely elated - it is as though a huge burden has been lifted,' he told the PA new agency.
Assange's mother, Christine Assange, said his release showed 'the importance and power of quiet diplomacy'.
'Many have used my son's situation to push their own agendas, so I am grateful to those unseen, hard-working people who put Julian's welfare first,' she said.
'The past 14 years has obviously taken a toll on me as a mother.'
Assange's wife Stella said while there had been uncertainty about the situation leading up to her husband being released from prison, she was 'elated' by the developments.
Assange's brother Gabriel Shipton told Reuters that for 'millions of people who have been advocating for Julian, it is almost time for them to have a drink and a celebration'.
Meanwhile, Mrs Assange late on Tuesday night made a public call for donations to pay the $US520,000 (about $A783,000) fee for the jet bringing her husband home.
