New Delhi: The showdown between the Opposition partied and President Pervez Musharraf is now heading for a climax ahead of Saturday’s presidential polls.
More than 200 members of the national and provincial assemblies are expected to resign on Tuesday in a dramatic attempt to undermine the Electoral College that's set to re-elect Gen Musharraf.
The Opposition MPs staged a mass resignation on Tuesday in protest at Musharraf's bid to win another five-year term in power.
Musharraf's two rivals in Saturday's crunch presidential vote meanwhile filed new petitions in the Supreme Court challenging the key US ally's eligibility to stand for re-election.
More than 80 opposition MPs backed by hundreds of flag-waving supporters chanting "Go, Musharraf Go!" marched to parliament, where they submitted their resignations to the speaker of the national assembly, or lower house.
Musharraf, who seized control of the nuclear-armed Islamic republic in a bloodless coup in 1999, is expected to win as his allies dominate the national and federal parliaments that are conducting Saturday's vote.
But his opponents hope that the resignations of more than 80 MPs from the anti-Musharraf All Parties Democracy Movement will cast doubt on its legitimacy.
"We are handing over the resignations today because we consider the election of the president is illegal and unconstititional," senior alliance member Liaquat Baloch said, before he was cut short by the speaker.
The alliance includes the parties of former premier Nawaz Sharif -- the man whom Musharraf ousted -- and cricketer-turned politician Imran Khan, plus a clutch of hardline Islamic fundamentalist groups.
Ex-prime minister Benazir Bhutto's Pakistan People's Party is not part of the coalition, having held talks with Musharraf on a power-sharing deal which have since apparently stalled.
The MPs and around 600 supporters, most of whom waved the flags of the hardline Jamaat-e-Islami party, marched from a parliamentary apartment building in Islamabad to the nearby national assembly building.
They shouted slogans including "This is the end of your show. Go Musharraf, Go!" and "A friend of America is a traitor".
"This is the first step to discredit the election process," said Khan.
Around 125 provincial legislators will also submit their resignations in the assemblies of Pakistan's four provinces, alliance officials said.
Two candidates standing against Musharraf in the election meanwhile lodged appeals in the Supreme Court against his re-election, saying that the nomination papers he filed last week were invalid.
Former Supreme Court judge Wajihuddin Ahmad, who quit rather than swear allegiance to Musharraf after his 1999 coup, and Bhutto party vice chairman Makhdoom Amin Fahim both called for the vote to be halted.
Musharraf won a major legal victory in the Supreme Court on Friday when it threw out a plethora of opposition challenges and ruled that the president was eligible to seek another term while keeping his role as army chief.
Former commando Musharraf has said he will quit his military role before November 15 if he wins the election.
The legal victory for Musharraf was however followed the next day by a police crackdown on protesters in Islamabad that left dozens of lawyers and journalists needing hospital treatment.
Pakistan's Chief Justice Iftikhar Muhammad Chaudhry, who himself led major rallies after Musharraf tried to sack him in March, ordered the suspension on Monday of the capital's police chief and two other officials over the violence.
(With agency inputs)