JERUSALEM - President Bush took the occasion of Israel's 60th anniversary Thursday to compare his American political opponents with Nazi appeasers and brand them as too willing to negotiate with terrorists, remarks that Democratic presidential candidate Sen. Barack Obama reacted to instantly as an attack upon him.

"We have an obligation to call this what it is -- the false comfort of appeasement, which has been repeatedly discredited by history," Bush said in his 23-minute speech to Israel's parliament.

The president's pointed criticism appeared to be a veiled jab at Obama, who has suggested that the United States should talk with its adversaries, as well as at former President Jimmy Carter, who last month met with senior officials of the radical Palestinian group Hamas in Syria.

Though the White House denied that Bush was criticizing Obama, the senator's campaign fired back immediately, calling the president's remarks an "extraordinary politicization" of U.S. foreign policy.

"It is sad that President Bush would use a speech to the Knesset on the 60th anniversary of Israel's independence to launch a false political attack," the Illinois senator said in a statement.

"It is time to turn the page on eight years of policies that have strengthened Iran and failed to secure America or our ally Israel. Instead of tough talk and no action, we need to do what Kennedy, Nixon and Reagan did and use all elements of American power -- including tough, principled, and direct diplomacy -- to pressure countries like Iran and Syria."

Obama has been criticized by rivals Hillary Rodham Clinton and John McCain as naive for being willing to negotiate with radical world leaders.

Obama has said that he would be willing to meet without preconditions with leaders of Iran, North Korea and other hostile nations that the U.S. condemns as supporting terrorism.

Bush has tried to stay out of the 2008 presidential race, and White House spokeswoman Dana Perino said Thursday that he didn't mean to directly criticize Obama.