US President George W. Bush on Tuesday urged European allies to stick with the United States in Iraq, and the White House said it may seek a new UN resolution to help persuade Spain not to withdraw its troops.
"It's essential that we remain side-by-side with the Iraqi people," Bush told reporters during a meeting with Dutch Prime Minister Jan Peter Balkenende.
"Al Qaeda understands the stakes. Al Qaeda wants us out of Iraq because al Qaeda wants to use Iraq as an example of defeating freedom and democracy," he said.
Bush's appeal for unity came one day after Spain's incoming leader, Jose Luis Rodriguez Zapatero, indicated he would pull his troops out of Iraq, in a major swing from his predecessor's pro-American foreign policy. The shift came just days after a suspected al Qaeda-linked strike killed 201 people in bomb attacks on Madrid trains.
White House spokesman Scott McClellan warned that Spain would be sending a "terrible message" if it let "terrorists" influence its policies.
He said Washington could seek a new UN resolution before it hands back sovereignty to Iraqis by the end of June, to encourage allies such as Spain to keep their troops in Iraq.
"We believe the United Nations has a vital role to play going forward," McClellan said. A new UN resolution "is something that certainly would be looked at," he said. "It may be quite appropriate, at that point."
Zapatero's Socialists swept to office on Sunday after last week's deadly Madrid train bombings.
"Terrorists must not be allowed to think that they influence elections or that they influence policy. That would be a terrible message to send," McClellan said.
Zapatero's victory was a setback for the Bush administration, which had received rock-solid support on Iraq from departing Spanish Prime Minister Jose Maria Aznar.
Bush said the goal of the terrorists was "to try to get the world to cower... to try to shake our will."
"They'll never shake the will of the United States. We understand the stakes and we will work with our friends to bring justice to the terrorists," Bush said.
"It is essential that the free world remain strong and resolute and determined," he added.
Bush appealed directly to the Dutch electorate not to withdraw their troops from Iraq.
"I would ask them to think about the Iraqi citizens, who don't want people to withdraw because they want to be free," Bush said.
"And I would remind the Dutch citizens that al Qaeda has an interest in Iraq for a reason, and that ... is they realise this is a front in the war on terror and they fear the spread of freedom and democracy in places like the greater Middle East," Bush added.
The Dutch government has said it will not be cowed into withdrawing its 1,100 troops from Iraq and that the attacks should not affect deliberations on extending their mandate.
Zapatero, due to take office within the next month, repeated several times on Monday his campaign pledge to pull out troops unless the United Nations gains more authority in Iraq - a shift in control that he said was unlikely.
Spain has 1,300 soldiers in parts of south-central Iraq. Critics of the government have argued that the Madrid bombings were the price Spain paid for backing the Iraq occupation.