Bush told the German newspaper Bild, "We need to take it seriously, and when he says he wants to destroy Israel, the world needs to take that very seriously."
The Iranian leader in the past has said Israel should be "wiped off the map."
Bush calls that "a threat to an ally of the United States and Germany." And the president adds "what he's also saying is, if he's willing to destroy one country, he'd be willing to destroy other countries."
The president says his first choice is use diplomacy in the the standoff with Iran over its nuclear program.
Bush told ARD German television, "an armed Iran will be a threat to peace."