Two-time ex-premier Nawaz Sharif, after talks with his coalition partner Asif Ali Zardari earlier this month in Dubai, had previously announced the judges would be restored on Monday.

Zardari, who is the widower of slain ex-premier Benazir Bhutto and now co-chairs her Pakistan Peoples Party (PPP), again met Sharif in London this week to resolve the issue, which threatens their fragile alliance.

Sharif's PML-N party spokesman put the blame for the deadlock on Zardari's party.

‘The ball is in the court of PPP. We have tried our level best... but so far no achievement has been made,’ Sharif's party spokesman Siddiqul Farooq told AFP about the latest rounds of negotiations in London.

‘Of course we do not support a judiciary which is subservient to the executive,’ Farooq said, adding that Sharif would return to Islamabad on Monday morning.

Farooq, when asked if Musharraf was ready to accept reinstatement of all judges except the deposed chief justice, said that his party would not agree to a ‘pick and choose’ solution to the issue.

Musharraf imposed emergency rule and ousted chief justice Iftikhar Muhammad Chaudhry and dozens of other judges in November last year when it appeared they might overturn his re-election as president the previous month.

Farooq declined to say whether his party would quit the coalition, which came to power after Bhutto and Sharif trounced Musharraf's allies in February general elections.

‘There is no session of the national assembly tomorrow,’ he said when asked if the May 12 deadline would pass without reinstatement of judges.

Sharif had said that the national assembly will approve a resolution on May 12 and on the same day it would be followed by the official restoration of the judges.

PPP spokesman Farhatullah Babar however downplayed reports of a deadlock and said that ‘there is progress, there is hope.’

Babar said that party stalwarts from both sides held meetings till late Saturday night and had ‘narrowed down’ differences over the reinstatement of judges and independence of judiciary.

‘I cannot call it a deadlock. Some proposals have been exchanged,’ Babar told AFP.

Babar also said that national assembly was not meeting on Monday.

Meanwhile Prime Minister Syed Yousuf Raza Gilani reiterated his stand on the issue.

‘We are committed to the revival of judiciary but we won't take any step which is unconstitutional or illegal, or which may trigger a clash of institutions,’ the Associated Press of Pakistan quoted him as telling reporters in the eastern city of Lahore late Saturday.

Reinstatement of the judges is likely to cause a major headache for embattled former army chief Musharraf, who considers them hostile to his rule.