Obama sees catastrophe if al Qaeda gets atom bomb

WASHINGTON, April 13 (Reuters) - U.S. President Barack Obama will say it would be a catastrophe if al Qaeda obtained nuclear weapons, according to excerpts of his opening remarks on Tuesday at a summit to prevent nuclear terrorism.

"Two decades after the end of the Cold War, we face a cruel irony of history -- the risk of a nuclear confrontation between nations has gone down but the risk of a nuclear attack has gone up," Obama said in the excerpts released by the White House.