Secretary of Defense Jim Mattis announced on Tuesday the United States will resume military drills on the Korean Peninsula, ending a suspension of exercises that formally began after President Donald Trump met with North Korean dictator Kim Jong-un in June.

“We took the step to suspend several of the largest military exercises as a good faith measure. We have no plans to suspend any more,” Mattis said at a press conference on Tuesday.

“We are going to see how the negotiations go, and then we will calculate the future, how we go forward,” he added, delivering one of the most unambiguous indications to date that the Trump administration is not pleased with North Korea’s conduct of late.

The suspension of military exercises announced by President Trump after the Singapore summit with Kim came as a surprise to many observers — and quite a few members of the administration — because North Korea has long denounced U.S. military exercises as provocative dress rehearsals for an invasion.

The huge annual Ulchi Freedom Guardian exercise with South Korea, scheduled to begin in August, was canceled this year as part of President Trump’s good faith gesture.

According to Pentagon officials, only two other much smaller Korean Marine Exchange Program exercises were officially canceled this year due to the suspension. The Pentagon also stressed that the 28,500 American military personnel stationed in South Korea have continued their routine training.

The next large-scale exercises on the calendar would be Key Resolve and Foal Eagle, which are normally held in February but were suspended until April last year due to the Winter Olympics.

Mattis indicated that no firm dates for new exercises have been set.

“We’ll make decisions on that in consultation with State,” he said. “It’s all riding on Secretary Pompeo’s shoulders.”

Secretary of State Mike Pompeo was scheduled to be in North Korea this week, but his trip was abruptly canceled on Friday after North Korea sent him a belligerent letter and President Trump expressed frustration with the lack of progress in Pyongyang on denuclearization.