Mohamed Nasheed, seen in this file photo, has been taken back to prison.

AFP/Colombo

The Maldives has put former president Mohamed Nasheed back in jail a month after his 13-year prison sentence was commuted to house arrest, his party said on Monday.

The Maldivian Democratic Party (MDP) said police and prison officials clashed with its supporters as they removed Nasheed from his home in the capital Male and took him to the high-security prison island of Maafushi on Sunday night.

"Nasheed's transfer back to jail is in clear breach of the Maldives' constitution, which provides no provision for reversing a commutation of a sentence," the MDP said.

Nasheed, the archipelago's first democratically-elected leader, was sentenced to 13 years in jail in March after a court convicted him under tough anti-terror laws.

The charges relate to the arrest of a judge accused of corruption when Nasheed, who was toppled in February 2012, was president.

Supporters of the former leader maintain his conviction was an attempt by the regime of President Abdulla Yameen to silence him.

Nasheed's sentence was formally commuted to house arrest on July 19 and it is not clear why he was taken back to prison.

He had earlier been moved to the main island of Male to receive medical treatment under an apparent deal with the Maldives government after closed-door talks with the opposition MDP aimed at ending political unrest in the honeymoon islands.

International criticism

Authorities had said they would appeal against Nasheed's conviction for terrorism, which drew heavy international criticism.

The MDP has since called on President Yameen to honour commitments made in the talks to release high-profile political prisoners including Nasheed and to quash criminal charges against some 1,700 dissidents.

The party said it had honoured its side of the bargain by providing parliamentary support for the sacking of Yameen's vice president Mohamed Jameel on treason charges, among other matters.

It also supported a controversial legal change that would allow foreign ownership of land for the first time in the Indian Ocean archipelago.

US Secretary of State John Kerry warned in May that democracy in the Maldives was under threat, saying Nasheed had been "imprisoned without due process".

Nasheed's lawyers resigned before the end of his trial, saying it was aimed at destroying his career, and the UN termed his jailing "vastly unfair".

It came at a time of growing opposition to the government of Yameen, who beat Nasheed in a run-off presidential election in late 2013.

Nasheed, a climate change activist who was also imprisoned during the three-decade rule of former strongman Maumoon Abdul Gayoom, was elected president in 2008.

He then rose to international prominence by hosting a cabinet meeting underwater to draw attention to the dangers facing the islands' existence from global warming and rising sea levels.

Nasheed's international lawyer Jared Genser announced last month that the government of the Maldives had permanently moved the former president to house arrest for the balance of his 13-year term in prison.