Former Pakistan premier Nawaz Sharif has threatened to pull his Pakistan Muslim League-Nawaz party out of the ruling coalition and "sit in the opposition" if judges sacked by former president Pervez Musharraf [Images] are not reinstated by Friday.

Sharif said he had gone along with his ally Pakistan People's Party co-chairman Asif Ali Zardari's move to impeach Musharraf before reinstating the deposed judges, even though he "wasn't convinced with his (Zardari's) arguments".

Now that Musharraf had resigned, the PML-N would have no option but to join the opposition if the judges are not restored, he said.

"If the judges are not restored we will perhaps be forced to sit in the opposition. We will not try to bring the government down. But of course then we have no choice but to sit in the opposition," Sharif, whose party is the second largest group in the PPP-led coalition, told the Wall Street Journal in an interview.

The coalition between the PPP and PML-N "came into being on the basis that democracy would be strengthened and judges restored," he said. "And of course, we will restore the Constitution as it stood before Musharraf overthrew an elected government."

Sharif, whose government was overthrown by Musharraf in a bloodless coup in 1999, said Zardari had insisted on impeaching the president first.

"Although I wasn't convinced with his arguments, I went along. I asked if the judges would be reinstated within 24 hours of impeachment, and he said yes," Sharif said.

"We produced that in writing. So we supported him on impeachment. It's now his turn to support us on reinstatement
of judges," he added.

Musharraf resigned on Monday to avoid impeachment by the coalition. Since then, Zardari and Sharif have held two rounds of talks but were unable to bridge their differences.

Observers believe Zardari is not keen on reinstating the judges as deposed Supreme Court chief justice Iftikhar Muhammad Chaudhry could scrap the National Reconciliation Ordinance, a controversial law issued by Musharraf to scrap graft charges against PPP leaders.

Chaudhry might also initiate cases against Musharraf, who has reportedly been given a "safe exit" in exchange for his resignation.

Sharif walked out of his last round of parleys with Zardari in Islamabad [Images] on Tuesday and went to his home in Lahore [Images].

The PML-N subsequently agreed to wait till Friday for an agreement on reinstating the judges.

The PML-N chief said it would "be a bad day for democracy" if judges are not restored as it would mean that the coalition was accepting "whatever the dictator did".

Sharif also said a "lot of people" from the opposition PML-Q, which largely comprises PML-N members who split from the party to support Musharraf when he seized power in a military coup in 1999, wanted to "rejoin the parent party."

He, however, said he had no intention of outnumbering the PPP by inducting the PML-Q members.

"I would very much like to see this coalition stay intact. But this coalition wasn't without an agenda. And that agenda is strengthening democracy, the rule of law and to restore the constitution and judges," he said.

"The judges were removed without any constitutional authority. So if we don't restore them, what are we doing? That's the core issue," Sharif added.

Asked if he wanted Musharraf to face trial following his resignation, Sharif said, he did not believe in politics of revenge and has no scores to settle with the ex-military dictator.

"But somebody who dismisses Parliament, subverts the Constitution, arrests the judges must tell the people why he did that. He must answer these questions under whatever forum the law provides," he said.

Replying to a question on whether he wanted to be prime minister again, Sharif said, "More important than being prime minister is to put this country back on the rails."

He also said he was not asking for the post of president "for myself or for my party. I would like to have a man of national consensus."