U.S. President Barack Obama says the U.S. and its allies and partners will continue pressuring North Korea to move in a new direction for denuclearization.

Obama said in his weekly radio address Saturday that Washington imposed stronger sanctions on Pyongyang early this year to deter the communist country from developing weapons of mass destruction.

He urged Iran, North Korea and other nuclear aspirants to take responsibility for arms reduction, citing the U.S. adherence to a bilateral deal with Russia on reducing nuclear warheads.

Obama had warned the North and Iran in a speech at the U.N. General Assembly earlier in the week that they must take responsibility if they continue with their nuclear ambitions.