Romano Prodi promised today to withdraw Italian troops from Iraq, saying that the allied invasion had been a grave mistake.

Signor Prodi was making his first speech as Italian Prime Minister to his country's Senate, where tomorrow he faces a no confidence vote, a mere 48 hours after he was sworn in.

"We consider the war and occupation in Iraq a grave error that hasn’t solved but has complicated the problem of security," he said. "Terrorism has found a new base, and new excuses for internal and external terrorist action."

As opposition leader, Signor Prodi opposed the war in Iraq and had said during the election campaign that the remaining troops would be pulled out "as soon as possible".

The government of Silvio Berlusconi, the conservative former prime minister, sent about 3,000 troops to Iraq to help reconstruction after Saddam Hussein was deposed in 2003.

The move was unpopular with Italians, and the contingent is already being pulled out gradually. Withdrawal is due be completed by the end of the year, unless Signor Prodi speeds it up.

Controversy over the troop deployment flared when 19 Italian carabinieri and nine Iraqis died as a suicide car bomber attacked the Italian military police base in Nasiriyah in November 2003.

The row was fuelled in February 2005, when US troops shot dead Nicola Calipari, an Italian secret service agent, at a security checkpoint in Baghdad as he escorted an Italian woman hostage to safety.

Today he did not give a precise timeline for the withdrawal, saying only it would happen in consultation with Iraqi authorities.

Signor Prodi was today moving to stamp his own authority and policies on government.

As part of this process he is expected in the coming days to signal a reverse on several of Signor Berlusconi's pet projects - including the enormous, €4 billion project to link the Italian mainland with the island of Sicily via a bridge over the Straits of Messina.

The contract was awarded at the end of last year in one of the last actions of the Berlusconi government, but construction has yet to begin in earnest.

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