NAJAF, Jan 29, 2005 (Reuters) - A senior Shi'ite cleric urged Iraqis on Saturday to boycott Sunday's landmark elections and take up arms to expel U.S. forces from the country.

"The current elections are a conspiracy to divide and destroy Iraq," Ayatollah Ahmed al-Hassani al-Baghdadi told Reuters on the eve of Iraq's first multi-party poll in 50 years.

Baghdadi, one of the few Shi'ite clerics openly to oppose an election that is expected to cement the long-oppressed Shi'ite majority's newfound political power, said a timeline for the withdrawal of U.S. troops and scrapping the interim constitution that embraces federalism should precede a poll.

"I believe these elections will fail as most Iraqis will boycott because of the lack of security and calls for federalism ... I call on my people to boycott the elections," he said in an interview at his home in Najaf.

Iraq's most influential cleric, Grand Ayatollah Ali Sistani, along with much of the Shi'ite religious establishment, has been a driving force behind the elections, issuing religious edicts ordering the faithful to cast their ballots.

Many in the southern holy city of Najaf, the spiritual home of Shi'ite Islam, plan to vote for a joint list of Shi'ite Islamist parties drawn up under Sistani's auspices.

But Baghdadi, exiled for years in Syria and Lebanon, has issued an edict opposing Sistani and demanding an election boycott by the faithful.

While he has far less influence than Sistani, who is deeply revered among Shi'ites, Baghdadi's rejection of elections reflects the simmering resentment of some Shi'ites for U.S. forces in the country, which face an insurgency led by Sunni militants and Saddam Hussein loyalists.

In April and August last year, the militia of fiery young cleric Moqtada al-Sadr, who comes from a family of respected Shi'ite scholars, battled U.S. forces in Najaf.

The U.S. military says it killed 1,500 of Sadr's fighters in the August battle, which ended when Sistani returned from medical treatment abroad and brokered a truce.

Sadr's movement is not officially running in Sunday's polls, but has not told followers to boycott them, though some plan to do so.

But many of the Sunnis who make up about 20 percent of the population, facing violence and intimidation in their heartland and feeling increasingly marginalized since the U.S.-led war, are leading a boycott.

Baghdadi condemned elections under the gaze of U.S. tanks as a mockery, slammed the cleric-politicians who are running for office and urged Iraqis to unite to expel American forces.

"Resistance will continue even if both Sunnis and Shi'ites go to the polls," he said. "These elections will fail. Elections with lax security, under the interim constitution, have no legitimacy."

"I am a son of Iraq and I call on all Christians and Muslims to expel the Americans from Iraq," he added.

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