KUALA LUMPUR - Malaysia's freed politician Anwar Ibrahim has said he will not serve in the Pakatan Harapan's new government for now, as he needs "time and space" to rest with his family and to travel abroad to fulfil teaching and speaking engagements.

"I will be kept informed but I don't need to serve in the Cabinet for now," he said, after being asked if he would have a role in the new Cabinet.

Datuk Seri Anwar, a former deputy prime minister, was speaking to reporters at his home in Segambut, Kuala Lumpur on Wednesday (May 16) after receiving a royal pardon from the King that morning.

Malaysia's most well-known prisoner walked out of the Cheras Rehabilitation Hospital in Kuala Lumpur at 11.30am, as crowds of supporters cheered and shouted chants of "Reformasi!", the battle cry of those protesting his sacking in 1998 and subsequent conviction for sodomy and abuse of power.

Mr Anwar, who was serving a second prison term for sodomy before Wednesday's release, has always maintained the charges against him were part of a conspiracy to end his political career.

The leader of Parti Keadilan Rakyat (PKR) left hospital to head to the palace, where he was granted an audience with the King at noon, together with Selangor Menteri Besar Azmin Ali and Deputy Prime Minister Wan Azizah Wan Ismail.

Mr Anwar was greeted by Prime Minister Mahathir Mohamad on his arrival at the palace. After a one-hour meeting with the King, the 70-year-old politician left the palace for his home.

At the press conference in his home, Mr Anwar said he would give Dr Mahathir and his wife Datuk Seri Wan Azizah all the support necessary to ensure changes for reform are effectively carried out.

He also thanked the King "for taking the immediate and firm decision" to release him without any conditions. He said the prison authorities had informed him that his criminal record has been completely erased.

In an interview with Australia's Fairfax Media published on Wednesday, Mr Anwar said his country was on the verge of a new "golden era", as the toppling of Barisan Nasional offered hope to people "clamouring for freedom" everywhere.

But he also cautioned that "one election does not a democracy make".

"I always believed in the wisdom of the people and that if we fought hard enough we would eventually prevail," he said.

"At a time when democracy is in retreat around the world, I hope that the people of Malaysia have given some hope to people around the world clamouring for their own freedom."

On Tuesday, PKR vice-president Nurul Izzah Anwar told reporters that her father's impending release was one of the best gifts to the family.

"We have missed so many Ramadans and I think that this is the sweetest gift ever for the family and the people of Permatang Pauh," she was quoted by Malaysian news website the News Straits Times Online.

Mr Anwar, who had been in hospital for the last few months following a shoulder operation, was serving a five-year jail term for his second sodomy charge.

He was previously scheduled to be released from prison on June 8, but this was expedited after the new Prime Minister, Tun Dr Mahathir Mohamad, who leads the PH government, took over Putrajaya.

Mr Anwar's release came seven days after the coalition formed the federal government, following its stunning victory in Malaysia's general election on May 9.

In 2008, Mr Anwar was dramatically arrested by policemen in balaclavas who hauled him from his car over accusations that he had sodomised his male aide, in an uncanny repeat of 1998 when he was arrested on similar charges.

He and his supporters have said the charges are politically motivated.

Receiving a full royal pardon does not only grant him freedom from prison; he is also free to take part in politics without having to complete a five-year ban on public office after his release.

"Freeing Anwar was a long time coming and while people in Malaysia and around the world are delighted, no one should forget the injustice he faced serving a long sentence for a crime that should never been considered a crime," said Phil Robertson, Deputy Asia Director, Human Rights Watch.

"The new Pakatan Harapan government should now get busy revising or revoking the many rights abusing laws that are still on the books in Malaysia so that other politicians and activists do not suffer a similar injustice to what Anwar faced."

PH, a four-party alliance led by Dr Mahathir, ousted the Barisan Nasional coalition for the first time in Malaysian history.

Dr Mahathir was sworn in as Prime Minister, for the second time in his career, but has pledged to step aside after two years and hand over the reins to his one-time deputy, Mr Anwar, once he is pardoned.

Mr Anwar began his five-year jail sentence in February 2015 after the Federal Court upheld his guilty verdict on the charge of sodomising his male aide Saiful Bukhari Azlan.