Playing down predictions that Iraq is headed toward civil war, President Bush said Saturday that he's optimistic a new government will unify the nation. He denounced any moves by Iran or Syria to interfere in Iraq's effort to build a democracy.

"I'm optimistic that the leadership recognizes that sectarian violence will undermine the capacity for them to self-govern," Bush said. "I believe we'll have a unity government in place that will help move the process forward."

The president's hopeful words came a day after Iraqi President Jalal Talabani called the new parliament into session March 19 for the first time since it was elected nearly three months ago. Talabani said he feared "catastrophe" and "civil war" if politicians could not put aside their differences.

Also on Friday, the State Department announced the discovery of the body of Tom Fox, 54, of Clear Brook, Va., one of four Christian Peacemakers activists kidnapped last year in Iraq.

"I fully recognize that the nature of the enemy is such that they want to convince the world that we cannot succeed in Iraq," Bush said Saturday about the continuing violence in Iraq. "I know we're going to succeed if we don't lose our will."

The president also said that while Iraq's security forces need more training, they performed well after the Feb. 22 bombing of a Shiite mosque, which led to the deaths of hundreds and pushed the country to the brink of civil war.

"There are some people trying to, obviously, foment sectarian violence — some have called it civil war — but it didn't work," Bush said. "Secondly, I'm optimistic that the Iraqi security forces performed — in most cases — really well to provide security. All but two provinces after the blowing up of the mosque were settled."

Bush spoke in the Roosevelt Room at the White House after receiving a briefing about the remote-controlled, homemade bombs that Iraqi insurgents conceal in cars or set off along roads. The devices are the leading killer of U.S. troops in Iraq.

Joining the president were Vice President Dick Cheney, Defense Secretary Donald H. Rumsfeld and Montgomery Meigs, a retired Army general who is leading the effort to find ways to counter the devices.

The United States alleges that the Syrians are aiding the insurgency by allowing foreign fighters to cross their border into western Iraq. Washington also claims the Iranians are encouraging radicalism among Iraq's Shiites and permitting bomb-making materials to cross its border

"If the Iranians are trying to influence the outcome of the political process, or the outcome of the security situation there, we're letting them know our displeasure," Bush said. "Our call is for those in the neighborhood to allow Iraq to develop a democracy, and that includes our call to Iran as well as to Syria."