Bush also urged Israel to exercise "the greatest possible care" in avoiding civilian casualties as it pounds targets in Lebanon in an effort to wipe out the Hezbollah Shiite militia that has been firing rockets into Israel.
At the same time, Bush blamed Hezbollah for touching off the crisis and said in his weekly radio address: "I believe sovereign nations have the right to defend their people from terrorist attack, and to take the necessary action to prevent those attacks."
The US president’s comments came after Rice announced that she would travel to the Middle East, to meet Israeli Prime Minister Ehud Olmert and Palestinian leader Mahmud Abbas, before heading to Rome for an international conference on the violence paralysing Lebanon.
"Secretary Rice will make it clear that resolving the crisis demands confronting the terrorist group that launched the attacks and the nations that support it," Bush said.
He said Syria was "a primary sponsor" of Hezbollah and has given the Shiite militia Iranian-made weapons, and he criticized Iran’s "ambition for nuclear weapons and aid to terrorist groups."
"Their actions threaten the entire Middle East and stand in the way of resolving the current crisis and bringing lasting peace to this troubled region," said the US president.
"Were also concerned about the impact the current conflict is having on Lebanons young democracy," he said. "Hezbollahs practice of hiding rockets in civilian neighborhoods, and its efforts to undermine the democratically elected government, have shown it to be no friend of Lebanon.
"By its actions, Hezbollah has jeopardized Lebanons tremendous advances and betrayed the Lebanese people," said Bush, who added that Washington would join efforts to get humanitarian aid to the Lebanese people.