Salih, in London for talks with British Prime Minister Tony Blair and other British ministers, made clear his anxiety about the change in tone in London and Washington, where senior figures are questioning whether the current strategy in Iraq is viable.
"I'm obviously concerned about the debate both in the U.S. and Europe, I have to say, because there is too much of a pessimistic tone to this debate -- even I would say in certain circles a defeatist tone," he told BBC radio.
"We need to be realist but not defeatist. We need to understand that there is a need of utmost urgency to deal with many of the problems of Iraq but we must not give in to panic."
U.S. military deaths in Iraq in October have reached 83, making it the most deadly month for Americans this year and raising pressure on President George W. Bush before Congressional elections next month in which Republicans could lose majorities in both houses.
U.S. military officials in Iraq have admitted that a two-month plan to secure Baghdad has failed to curb violence.
In Britain, army chief General Richard Dannatt sparked a political storm this month by saying British troops should withdraw from Iraq soon as their presence was worsening the security situation there and in the wider world.
Salih said the current situation in Iraq could not go on.