President Lech Kaczynski said the ramifications of such a withdrawal must be thought through before any decision is made, he said in an interview with Rzeczpospolita daily.
"I am afraid of a second Vietnam, when the Soviet Union tried to use the U.S. defeat and conquer the world," Kaczynski reportedly said, citing several countries in which the Soviets used direct military involvement or supported proxy forces following the end of the Vietnam conflict.
"The Soviet Union does not exist anymore, but there are other forces, capable of provoking large-scale conflicts in the world," he reportedly said, without being more specific.
Poland is a part of a "huge international society" that wants to defend its security, he said.
"Unfortunately, that must have a price," Kaczynski was quoted as saying.
Poland sent troops to the 2003 U.S.-led war in Iraq and still has some 900 soldiers there. It has lost 21 troops.
He reiterated that Poland will not "run away," despite a recent attack in which Poland's ambassador to Iraq was injured and again emphasized that any pullout plan "must be concerted with the solutions taken by the main nation taking part in this."
Kaczynski, whose five-year term started in 2005, has authorized the Iraq mission through 2007 and has not officially decided to extend it.