Pakistan's opposition parties neared agreement Wednesday on joint demands for President Pervez Musharraf in return for calling off a boycott that could spoil the legitimacy of parliamentary elections next month, an official said.

The negotiations came as the government prepared to expel two U.S. rights activists who have protested the arrests of Supreme Court justices and leading lawyers since Musharraf introduced emergency rule Nov. 3.

The meeting between representatives of former prime ministers Benazir Bhutto and Nawaz Sharif and other smaller parties are crucial to an opposition push to challenge Musharraf's political dominance. Bhutto spent the day meeting with foreign ambassadors, including the U.S., British and Saudi envoys.

Opposition leaders have threatened to boycott the Jan. 8 vote, undercutting the efforts of Musharraf — a key U.S. ally in the war on terror — to ease Pakistan back toward democracy after eight years of military rule.

The parties are demanding the end of emergency rule and the release of the justices, who were sacked amid indications that they were preparing to invalidate Musharraf's re-election in October by the outgoing parliament.

Chaudhry Shujaat Hussain, chairman of the ruling Pakistan Muslim League, dismissed the opposition demands as unrealistic.

"In fact, the two alliances have nothing to attract people and are therefore raising non-issues," he was quoted as saying by the state-run Associated Press of Pakistan news agency.

Sharif and Bhutto, long-standing political foes, have been drawn together since returning from exile by the common goal of confronting Musharraf. Their move to formulate a joint set of conditions raises the stakes for the government, which they accuse of planning to conduct a sham election.

Ahsan Iqbal, spokesman for Sharif's Pakistan Muslim League-N, said issues under consideration include restoration of an independent judiciary and the constitution, and creation of a neutral caretaker government and an independent election commission, along with a deadline for the government to accept the demands.

"The present situation demands that all democratic forces work in unity and collectively to save the country from a major catastrophe which will result after rigged elections," Iqbal said.

But another politician, former cricket star Imran Khan, insisted that the opposition should boycott the ballot.

"You do not have elections when fundamental rights are suspended," Khan told Dawn Television. "Never has any judiciary been butchered as it has been in Pakistan (and) by taking part in elections we would legitimize everything Musharraf has done."

Under emergency rule, Musharraf has filled the Supreme Court with loyalists and jailed hundreds of human rights workers, civic activists and lawyers.

Most have since been released and Musharraf has promised to lift the emergency Dec. 16, about three weeks before the elections. But repression continues.

The Human Rights Commission of Pakistan urged the public to mark next Monday as a "black day" by displaying black flags and wear black bands. It called 2007 one of the worst years for human rights in the country's history and rejected Musharraf's claims that he is restoring democracy as "a total farce."

"The rights of ordinary people have been violated by the government with impunity," the group said in a statement. "Reports of torture, threats, intimidation, and arbitrary arrests run into thousands. Incidents of extrajudicial killings are reported but never investigated. The situation has now reached alarming proportions. The media is chained and free expression censured."

On Tuesday, two U.S. human rights activists, identified as Medea Benjamin and Tighe Barry, were arrested in the eastern city of Lahore after holding protests and calling for the release of Aitzaz Ahsan, president of the Supreme Court Bar Association.

U.S. Embassy spokeswoman Elizabeth Colton said the two had been turned over to U.S. consular officials and were expected to leave Pakistan "in the next day or so."