A Pakistani court trying former military ruler Pervez Musharraf for treason has ordered the government to add a former prime minister, law minister and chief justice to the charge sheet.

A special court ruled on Friday that the three civilians who served under the former president should also stand trial for suspending the constitution and imposing emergency rule in 2007.

Two judges ruled that Shaukat Aziz, then-law minister Zahid Hamid and judge Abdul Hameed Dogar, who was elevated to chief justice, should also be tried, lawyers said.

Musharraf's lawyers, who had applied to have the charge sheet expanded to include around 600 other names, welcomed the decision.

"We always maintained this stance that he was not alone, there were many co-accused with him," Chaudhry Faisal Hussain, told reporters outside the court in Islamabad.

"So now the court, after sifting through the evidence, has come to the conclusion that yes, there were some co-accused." 

Musharraf, who faces death or life imprisonment, has pleaded not guilty to the treason charges, and has repeatedly denounced the case as a "vendetta" against him.

The move will further prolong proceedings against Musharraf, 71, who returned to Pakistan last April vowing to run in the general election to "save" the country from a Taliban insurgency and economic ruin.

Constant delays

The case suffered repeated delays earlier this year due to Musharraf's health problems and alleged security threats against him.

Pervez Musharraf: 'A politicised vendetta'

"The government, or any other co-accused who are to be included in the case, can go to the Supreme Court and if this happens there will be long and time-consuming arguments there," former deputy attorney general Raja Abdul Rehman told the AFP news agency.

The case against Musharraf dates back to his 1999-2008 rule and his decision to impose emergency rule while he was still army chief.

Musharraf overthrew elected Prime Minister Nawaz Sharif in a bloodless coup in 1999, but a year later the Supreme Court validated the take over. Musharraf then served as president from 2001 to 2008.

During the 2007 emergency rule he suspended the constitution and parliament, and sacked top judges who declared his actions unconstitutional and illegal.

Since Musharraf was indicted in March, there have been regular rumours of a backroom deal to allow him to leave Pakistan to avoid a destabilising confrontation between the government and the army.

Source: Al Jazeera and agencies