(Top) Nawaz Sharif in Lahore and Benazir Bhutto in Larkana, Sindh, after filing nomination papers for the coming elections. (AFP, AP)

Lahore, Nov. 26 (Reuters): Former Pakistani Prime Ministers Benazir Bhutto and Nawaz Sharif signed up today to run in a January election.

Both Sharif and Bhutto said they might yet boycott the January 8 general election, which is being organised under emergency rule that US ally Musharraf imposed on November 3, largely to derail legal challenges to his bid to secure another term.

Sharif, ousted by President Musharraf eight years ago, flew home from Saudi Arabia yesterday, saying Musharraf had taken the country to the brink of disaster.

Two-time Prime Minister Sharif said he would not be a candidate for Prime Minister under Musharraf, who had to reinstate the judges he purged after declaring the emergency. Sharif also said he retained the option of boycotting the elections.

“We don’t want to boycott elections, but if you push somebody to the wall, then what are the options left?” Sharif said at a news conference in Lahore.

“The boycott remains a very potent option for the Opposition,” said Sharif, who was deported when he tried to come back in September.

But the political atmosphere has changed radically since then with Musharraf’s imposition of an emergency and the apparent breakdown of efforts to forge cooperation between him and Bhutto.

Bhutto, who came home from eight years in self-imposed exile last month, filed her election papers in her family’s hometown of Larkana in the southern province of Sindh.

Western governments fear Musharraf’s emergency rule and moves to stifle democracy in Pakistan could give an advantage to Islamist militants.

There have been more than 25 suicide attacks since Islamist militants intensified a campaign in July. The latest two killed 15 people in Rawalpindi on Saturday.

Bhutto said her party would be taking part in the elections under protest.

“We felt that if we don’t do that, then it will leave the field open for the regime and they will not need to rig the elections,” Bhutto said by telephone from Larkana after filing her nomination papers.

She said Sharif’s return was a positive step and it would put pressure on Musharraf's ruling party.