Pakistan's Supreme Court is expected to deliver a verdict later this week in a contempt case against the prime minister that could see him losing his job at a time when his U.S.-backed government is fighting terrorism and militancy, the premier's lawyer said Tuesday.

A guilty verdict could also result in Prime Minister Yousuf Raza Gilani serving up to six months in prison for his refusal to reopen an old corruption case against the country's president, his political ally.

That could stoke fresh political turmoil at a time when Pakistan is trying to patch up its relations with the United States and is grappling with a weak economy and a bloody Taliban insurgency.

But even if Gilani is forced to step down — a process that could take months — the deeper political impact could be limited since the ruling coalition has the majority in parliament needed to elect a new prime minister.

The court has summoned to Gilani to appear before it on Thursday, when it is expected to deliver its verdict, said his lawyer, Aitzaz Ahsan.

"I am hopeful that the prime minister will be acquitted," Ahsan told reporters outside the courthouse in Islamabad.

The judges have repeatedly ordered the government to write a letter to Swiss authorities requesting they reopen a graft case against President Asif Ali Zardari that dates back to the late 1990s.

Gilani has refused, saying the president enjoys immunity from criminal prosecution while in office. He and other members of the ruling Pakistan People's Party have argued that the Supreme Court has relentlessly pursued the case because of bad blood between Chief Justice Iftikhar Mohammad Chaudry and Zardari.

Also Tuesday, a bomb went off at a railway station in the city of Lahore, killing three people and wounding more than 20 others, police official Manzoor Ahemd said.

He said the bomb went off outside a waiting room of the station in Lahore, the capital of eastern Punjab province.

Although Pakistan has witnessed scores of bomb blasts in recent years, such attacks at railway stations are rare.


Associated Press writer Munir Ahmed contributed to this report.