Pakistani lawyers and former prime minister Nawaz Sharif took to the streets on Thursday to demand President Pervez Musharraf reinstate sacked judges.

Police in riot gear manning barbed wire barricades blocked scores of lawyers opposed to Musharraf as they tried to approach the Islamabad home of deposed chief justice Iftikhar Chaudhry.

Sharif, who is calling for a boycott of a January general election unless judges Musharraf purged to safeguard his re-election are reinstated, also tried in vain to visit Chaudhry.

Sharif's supporters showered him with rose petals and some, chanting Go, Musharraf, Go!, tore down a roadside banner picturing Musharraf, punching it and slapping it with their sandals. They then tried to burn it.

Opposition leader Benazir Bhutto tried to visit Chaudhry last month, and was also blocked.

Sharif and Bhutto's parties are still negotiating over demands they plan to issue Musharraf on pain of an opposition election boycott.

A boycott by the two main opposition parties and smaller allies would rob the January 8 vote of credibility and prolong instability in a nuclear-armed country that is crucial to U.S. efforts to fight al Qaeda and bring peace to neighboring Afghanistan.

HAGGLING OVER JUDGES

Opposition officials said the two parties differed over whether to demand the restoration of 37 judges, including Chaudhry, dismissed by Musharraf after he imposed emergency rule on November 3.

Bhutto says the new parliament should decide on the fate of the judges.

There is no question of compromise on this issue. We are saying it should be before the election. The PPP says it should be after the election, said Javed Hashmi, a senior official in Sharif's party tipped as a possible candidate for prime minister, referring to Bhutto's Pakistan People's Party.

This is the only thing where we have to this time not been able to agree, Hashmi said.

Bhutto has said her party would reluctantly take part in the vote, while reserving the right to withdraw or to protest against an unfair result. She has already issued a manifesto and effectively kicked of her campaign last weekend.

Despite his doubts about the election, Sharif registered to run but his nomination was rejected on Monday because of criminal convictions he says were politically motivated.

Bhutto returned from eight years of self-exile in October. Sharif, ousted by Musharraf in 1999 and sent into exile the following year, came home on November 25.

Musharraf stepped down as army chief last week and was sworn in as civilian president. He also promised that emergency rule would be lifted on December 16, fulfilling two main demands of his rivals and his Western backers.

But Musharraf has ruled out reinstating the judges, several of whom remain under house arrest. Musharraf has been at odds with the judiciary since he tried to sack Chaudhry in March.

Musharraf justified the emergency citing interference by the judiciary and rising militancy, particularly in the northwestern valley of Swat. The army launched an offensive there last month to drive out insurgents.

(Additional reporting by Zeeshan Haider; Editing by Bill Tarrant)

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