Seven weeks of unrelenting anti-government protests and defections among the ruling elite have piled pressure on Ali Abdullah Saleh to step down immediately after 32 years in power.

But an aide said he would leave office only after organizing parliamentary polls and establishing democratic institutions, by January 2012 -- a declaration the opposition promptly rejected.

In speeches to army officers and tribal leaders in Sanaa, Saleh said Yemen faced a danger of civil war and disintegration because of efforts to stage a "coup" against his rule.

"Those who want to climb up to power through coups should know that this is out of the question. The homeland will not be stable, there will be a civil war, a bloody war. They should carefully consider this," Saleh told army commanders.

The United States, grappling with the diplomatic fallout of uprisings and uncertainty across the Arab world, voiced rare public alarm about the situation in Yemen.

"We are obviously concerned about the instability in Yemen," U.S. Defense Secretary Robert Gates said. His chief concern was to avoid "diversion of attention" from opposing al Qaeda there.

Reuters