Pakistan moved on Monday to put former military dictator Pervez Musharraf on trial for treason for suspending the constitution and declaring a state of emergency while he was in power.

Musharraf has been embroiled in a complicated web of legal cases after returning to Pakistan this year from self-imposed exile to take part in a May election. His arrest was unprecedented in a country where the army wields enormous power.

He has been granted bail in three court causes in past weeks, prompting speculation that he would soon be able to leave the country. Musharraf has not publicly commented on the matter.

But on Monday, the government filed a request with the Supreme Court asking it to set up a panel to try Musharraf over accusations that he breached the constitution when he imposed emergency rule in 2007.

Observers believe the army wants to find a face-saving reason for his departure, possibly on grounds of ill health, but putting him on trial would be an unprecedented demonstration of power by Pakistan's fledgling civilian administration.

The army has ruled the nuclear-armed South Asian nation for more than half of its history since independence in 1947.

Musharraf, who lives in a villa near the capital, Islamabad, under tight security, was army chief when he took power in a 1999 coup. The current prime minister, Nawaz Sharif, was the one Musharraf ousted in that coup.

Musharraf stepped down after the party of assassinated former prime minister Benazir Bhutto won an election in 2008.

He returned to Pakistan in March after nearly four years of self-imposed exile to contest a May 11 general election, but he was disqualified from standing because of pending court cases.

The latest move by the government comes after Musharraf had filed an application with a regional court asking to waive restrictions on his movements so he could visit his ailing mother abroad.

The hearing of the application has been adjourned until November 22.