Obama promotes nuclear-free world

Apr. 5 - U.S. President Barack Obama says his country will take concrete steps to free the world of nuclear weapons.

U.S. President Barack Obama set out his vision for a world free of nuclear weapons on Sunday. Visiting the Czech capital on a one-week trip marking his presidential debut on the world stage, Obama said the U.S. would continue developing anti-missile defences as long as an Iranian nuclear threat remained.

He also called on Pyongyang to abandon its efforts to acquire nuclear weapons, after its rocket launch.

Sarah Barden reports.