More troops would be sent to Iraq if they were needed, British Foreign Secretary Jack Straw told the BBC on Thursday.
He told the BBC that troop numbers were being constantly reviewed.
Attacks like the one on the Italian police headquarters indicated that elements against the coalition were becoming increasingly organised, he said.
After talks with US Secretary of State Colin Powell in Washington, both men said they wanted an Iraqi administration in place "as soon as possible".
"That can only be done if Iraqis themselves consent to the process," he said at a press conference with Powell.