Prime Minister Mohammad Nawaz Sharif said Monday former President Pervez Musharraf would be prosecuted on a charge of treason punishable by death.
"Musharraf has to answer for his deeds," Sharif told the National Assembly of the government decision to prosecute Musharraf at the Supreme Court for abrogating the Constitution in 2007 when he was in power.
Musharraf, who returned to Pakistan in March this year to take part in May's general elections, has been under house arrest at his farmhouse in Islamabad.
Musharraf suspended the Constitution on Nov. 3, 2007, when he imposed emergency rule and imprisoned Supreme Court judges.
The Supreme Court has declared Musharraf's move an act of treason and directed the government to proceed against him.
A lawyer representing Musharraf said prosecuting the former Army chief on a treason charge would open a "Pandora's box" in Pakistani politics.
"There is no treason case against Pervez Musharraf. He had acted in the interest of the nation," the lawyer, Ahmad Raza Kasuri, told reporters outside the Supreme Court building.
Musharraf seized power in a bloodless coup in October 2009 that overthrew the government of Nawaz Sharif.
Musharraf had tried Sharif on charges of hijacking an aircraft in which Musharraf was traveling. The crime was punishable with death but the courts gave a prison term to Sharif.
Sharif was ultimately allowed to leave Pakistan under an agreement brokered by Saudi Arabia. He returned to power after the May 11 general elections.
Musharraf stepped down as president in August 2008, about six months after his allies lost parliamentary elections and the government threatened to impeach him. A year later, he left the country.