Spanish Prime Minister Jose Maria Aznar has paid a surprise visit to Spanish troops in Iraq.
Many in Spain feel the country's troops should not be in Iraq
He and a 17-member delegation travelled to the southern town of Diwaniya, where the 1,300-strong contingent is based.
In a televised Christmas message to Spanish troops, Mr Aznar said: "You are working for a world that is more free, more stable and more safe."
Spain has been one of the staunchest allies of the US in the war in Iraq, despite domestic opposition.
Mr Aznar was scheduled to leave after having lunch with the soldiers, his office said.
Last month, seven Spanish intelligence officers were killed in a rocket attack outside Baghdad. Spain has also lost 10 of its soldiers stationed in the country.
Mr Aznar's visit came amid reports that US troops mistakenly killed three Iraqi police in northern Iraq. The police manning a checkpoint near Kirkuk were thought to be insurgents, local police said.
The US military says it is still investigating the incident.
Iraqi police say two of the dead policemen's colleagues were seriously wounded in the incident.
The police in Iraq have been a frequent target of insurgents.
At least 116 have been killed since the fall of Saddam Hussein, the British military says.
In another development, two former officials of Saddam Hussein's
Baath party have been attacked and one of them killed in the Shia holy city of Najaf.
One was shot dead along with her five-year-old son.
Damiyah Abbas is thought to have participated in the repression of a 1991 Shia uprising the regime of Saddam Hussein, reports say.
The other Baath official who was killed, Ali Kassem, was a
local city official, according to police.
But it is not the first time they have been attacked in error by US forces.
Ten members of the Iraqi security force were recently killed by American troops in Falluja.