Pakistan's Election Commission on Monday barred former prime minister and opposition leader Nawaz Sharif from a January 8 general election because of his criminal record.
Sharif, a two-time prime minister overthrown in 1999 by the then army chief, Pervez Musharraf, has been threatening to boycott the January 8 elections but had nonetheless registered to run.
His nomination papers are rejected because of his convictions, presiding election official Raja Qamaruzaman told Reuters in the eastern city of Lahore, Sharif's power base, where last week he filed his nomination.
Sharif, who returned from seven years of exile on November 25, says the convictions secured against him in the wake of his ouster were politically motivated.
He brushed off his disqualification and vowed to fight on against what he called dictatorship.
Let them reject the nominations ... 10 times or even 100 times. I will serve the people with much more vigor and resolve, he told his supporters.
His disqualification will be seen by the opposition as the result of pressure on election officials by President Musharraf, who critics say has sway over voting officials.
Musharraf is responsible for the disqualification of both Nawaz and Shahbaz. He wants to keep them out of the frame. This is the most blatant form of rigging possible, said Sharif's spokesman, Nadir Chaudri.
Election officials barred Sharif's brother, Shahbaz, from running last week citing financial irregularities.
Sharif was convicted of hijacking and terrorism and sentenced to life in prison in 2000 for trying to turn away an aircraft carrying Musharraf, whom Sharif had just dismissed as army chief, back from an overseas visit in October 1999.
The incident precipitated Musharraf's coup.
In July 2000, he was convicted on a corruption charge. He was sent into exile in Saudi Arabia later that year on condition, the government says, that he stay out of politics for 10 years.
The constitution bars convicted people from running for parliament.
Sharif arrived in Islamabad earlier on Monday for talks with another opposition leader and former prime minister, Benazir Bhutto, on his plan to boycott the vote.
Bhutto, who returned from eight years in self-exile in October, says her party will take part in the election, although she has left open the option of joining Sharif in a boycott.
Sharif and his allies, including the second biggest religious party and the small party of former cricket hero Imran Khan, say taking part in the election would legitimize Musharraf's unconstitutional maneuvers to hold on to power.
He is demanding that Musharraf reinstates the judges he dismissed after he declared emergency rule on November 3.
Bhutto says a boycott would leave the field open to Musharraf's allies who are expected to fare badly in the vote, putting a question mark over his long-term rule.
A united opposition boycott would rob the vote of credibility and prolong instability in the nuclear-armed country that is crucial to U.S. efforts to fight al Qaeda and bring peace to neighboring Afghanistan.
Musharraf has promised to lift the state of emergency by December 16 but he has ruled out reinstating the judges. When he imposed the emergency they were thought to be about to rule invalid his October re-election by legislators.
More than 5,000 activists detained under the emergency have been released but some judges, including the former chief justice who defied Musharraf's bid to dismiss him in March, are still under house arrest.
Visiting Turkish President Abdullah Gul, due to meet Bhutto and Sharif, said all leaders should behave constructively.
Democracy is essential for the sustainability of the states but at the same time, the realities of the country should be taken into consideration, Gul told a news conference.
Gul is the first foreign leader to visit since Musharraf, bowing to international pressure, stepped down as army chief and was sworn in as a civilian president last week.