North Korea on Tuesday suggested it might call off its 20-month suspension of nuclear and missile tests because of summertime U.S.-South Korean military drills that the North calls preparation for an eventual invasion.

The statement by the North’s Foreign Ministry comes amid a general deadlock in nuclear talks, but after an extraordinary meeting of the U.S. and North Korean leaders at the Korean border raised hopes that negotiations on the North’s growing nuclear and missile arsenal would soon resume.

The statement serves as a reminder of North Korea’s longstanding antipathy toward U.S.-South Korean military cooperation, which the allies call defensive and routine but the North sees as hostile. It also ramps up the pressure on the United States going into any new round of talks.