The U.S. military has no plans yet to suspend any more major military exercises with South Korea, the defense secretary said Tuesday amid a breakdown in diplomacy with North Korea over its nuclear weapons.

Defense Secretary Jim Mattis told a Pentagon news conference that no decisions had been made about major exercises for next year but noted that the suspension of drills this summer as a good-faith gesture to North Korea was not open-ended.

U.S. President Donald Trump's June decision to unilaterally suspend the drills caught many American military planners off guard and was broadly criticized as a premature concession to North Korean leader Kim Jong Un, who Trump wants to give up his nuclear weapons.