Updated

Spain started the process of pulling its forces out of Iraq on Monday, and Defense Minister Jose Bono (search) said the withdrawal of all 1,300 troops would be completed in less than six weeks.

"They'll be coming back very soon and safely," Bono told a press conference.

"It would be imprudent to talk of six to eight weeks because it's going to be less," he said of the time frame, and later specified the withdrawal would be complete within six weeks.

Bono spoke a day after newly elected Prime Minister Jose Luis Rodriguez Zapatero (search) announced he would fulfill his campaign promise to bring home troops unless the United Nations takes control of the occupation of Iraq by June 30.

Zapatero said he had determined that condition would not be met by the deadline, which is when the Spanish troops mandate expires.

A detachment of 194 Spanish troops left on Monday for Iraq, designated mostly to help with the planned withdrawal. The troops were initially supposed to go for a regular rotation; and 50 fewer soldiers than planned were sent.

President Bush lamented Spain's decision and cautioned Zapatero to avoid actions that might give "false comfort to terrorists or enemies of freedom in Iraq," White House press secretary Scott McClellan said.

Bono and Foreign Minister Miguel Angel Moratinos declined to comment on Bush's remarks, which Spanish media played up as confrontational, although Moratinos insisted that the United States, a firm ally of former conservative Prime Minister Jose Maria Aznar (search), was still "a friend and an Atlantic partner."

Australian and British leaders also regretted Spain's decision.

Moratinos planned to fly Tuesday to Washington to meet with U.S. Secretary of State Colin Powell and other officials after stopping first in Dublin, Ireland, to talk with European Union colleagues.

Outgoing President Jose Maria Aznar had been one of President Bush's staunches allies in Iraq, and has party was widely expected to win re-election despite public opposition of the invasion that ousted Saddam Hussein.

That changed with March 11 terrorist train bombings in Madrid that killed 191 people and injured more than 2,000 three days before the election -- an attack Al Qaeda leader Usama bin Laden later said was retribution for Spain's role in Iraq.

Zapatero's Socialists beat Aznar's conservative Popular Party in an upset, amid allegations that the government had concealed information pointing to Al Qaeda's carrying out the bombings, Spain's worst terror attack.

Critics have suggested that Zapatero's decision to withdraw troops was influenced by the attack, and therefore would give incentive to terrorists.

Bono insisted Monday that the withdrawal was "the fruit of a commitment the prime minister had with Spaniards and with peace. ... We weren't thinking about any event in particular."

In Iraq, radical cleric Muqtada al-Sadr called for a halt in attacks on Spanish troops in Iraq after the announced withdrawal.

Al-Sadr's office urged Iraqis to "maintain the safety of the Spanish forces until their return home" and urged "the governments of the other armies taking part in Iraq's occupation to follow the Spanish government's example."

Poland commands the 23-nation international peacekeeping force of 9,500 troops that includes Spain's 1,300. It will not be able to make up the difference itself, officials said Monday.

San Salvador's 380 troops in Iraq will remain, and serve under Polish command after the removal of Spanish forces, San Salvador's military said Monday. The Salvadorans have been part of the Spanish-led Plus Ultra brigade.

Spanish troops are mostly stationed in south-central Iraq with responsibility for Diwaniya and the Shiite holy city of Najaf. Eleven Spaniards have died since August, including seven intelligence agents killed in a highway ambush in November.