By Qasim Nauman and Serena Chaudhry
ISLAMABAD (Reuters) - Pakistan's Supreme Court on Thursday adjourned a contempt hearing for Prime Minister Yusuf Raza Gilani in a case that could push him from office and is adding to growing pressure on the unpopular civilian government.
Gilani was in court to explain why he should not be charged with contempt for failing to re-open old corruption cases against President Asif Ali Zardari. The government maintains Zardari has presidential immunity.
"It is my conviction that he (Zardari) has complete immunity inside and outside the country," Gilani told the court. "In the constitution, there is complete immunity for the president. There is no doubt about that."
The prime minister, however, appeared not to have convinced some judges.
"On the next date, let's hear you convince us the issue is of the president's immunity," said Justice Sarmad Osmani, a member of the seven-panel bench. "Let's grab the bull by its horns."
While the immediate battle is about Gilani, the larger political crisis is about Zardari -- who has had his own run-ins with the chief justice -- and the fate of his government which is also increasingly at loggerheads with the military.
It is the longest-running civilian administration in Pakistan's coup-marred history, but has become deeply unpopular, seen as both corrupt and incompetent.
If Gilani is charged with contempt of court, he could be disqualified from office and be forced to resign.
That would further increase the pressure on the government and the risk of more instability in the nuclear-armed ally in the U.S.-led war in Afghanistan.
After the hearing, a confident-looking Gilani appeared outside the court smiling and waving. The Supreme Court agreed that he would not have to appear again personally when it reconvenes on February 1.
Gilani's legal troubles are the latest blow for his administration which also faces pressure from the military over a mysterious memo seeking U.S. help to avert an alleged coup last year.
Ahead of the court hearing, police blocked off parts of the capital city to impose tighter security in the South Asian country facing homegrown Taliban militants blamed for many of the suicide bombings that have kept foreign investors away.
Hundreds of policemen were stationed outside the Supreme Court as every car was checked. Gilani's security men, in dark suits, combed the premises.
After the hearing, members of various bar associations chanted slogans in support of the court, whose chief justice has had poor relations with Zardari since the president opposed his return to the bench in 2007.
"We felt we had to come and support the judiciary, not let anyone intimidate them," Rana Umer Iqbal, 28, a lawyer from Islamabad told Reuters.
Zardari's court battles are often portrayed in the media and public debate as an assault on the court's independence, while his supporters say he is defending himself against bias.
During the 1990s, Zardari had multiple cases of corruption and even murder lodged against him, all of which he says are false and politically motivated.
An amnesty deal that protected him from prosecution was nullified in 2009 and the court has been pushing for the government to re-open and investigate the corruption cases against Zardari.
The government refuses to do so, saying Zardari enjoys immunity as the head of state.
In an exchange with the judges, Aitzaz Ahsan, the prime minister's lawyer, said the government could not write a letter to Swiss authorities to re-open the corruption cases.
"The letter shall be written when ... Asif Ali Zardari is no longer the president," Ahsan told the bench.
Gilani won a unanimous vote of confidence in parliament when he became prime minister nearly four years ago, and has been known as a peacemaker even among the ruling Pakistan People's Party's most bitter enemies. Unlike Zardari, he was seen as having smooth ties with the military before the latest turmoil.
But his diplomatic skills may not be enough to fend off both the Supreme Court and Pakistan's generals, who have ruled the country for more than half of its 64 years history through coups, and from behind the scenes.
"The fact is that it's not just the anger of the judges against the PM, it's the anger of the army against the PM as well," said Ayesha Siddiqa, a prominent defence analyst.
(Additional reporting by Rebecca Conway in ISLAMABAD, Sahar Ahmed and Faisal Aziz in KARACHI; Writing by Chris Allbritton; Editing by Jonathan Thatcher)