ANKARA

Washington threatened North Korea with “tougher sanctions” Wednesday if Pyongyang refused to destroy its nuclear program.

“If they're not willing to do it, President [Donald] Trump has been very clear they're not getting relief from the crushing economic sanctions that have been imposed on them," National Security Adviser John Bolton told the Fox Business Network on Tuesday. “And we'll look at ramping those sanctions up, in fact.”

Trump walked-out of a second summit with North Korean leader Kim Jong-un in the Vietnamese capital Feb. 28 with both sides giving contradictory accounts.

The U.S. president said North Korea “wanted sanctions to be lifted in entirety” but Pyongyang countered it insisted only on a partial lifting of sanctions.

“If Trump had accepted Kim's offer, it would have given North Korea a lifeline, giving them a chance to get their breath back economically while potentially still concealing a lot of nuclear weapons capabilities, missiles and the rest of it,” according to Bolton.

He said “the ball was in North Korea's court,” reiterating the U.S. wants dialogue and will wait for positive signs from Pyongyang.