South Korea and the United States are preparing to hold their annual joint military exercises despite warnings from North Korea that the drills could derail fragile nuclear diplomacy, Seoul’s military said Monday.

Choi Hyun-soo, spokeswoman of Seoul’s Defense Ministry, said the exercises will be focused on verifying Seoul’s capabilities for its planned retaking of wartime operational control of its troops from Washington. She did not confirm or deny reports that the drills, which are expected to be computer simulated and not involve actual combat troops and equipment, began on Monday.

North Korea recently has been ramping up its weapons tests, including two test firings of what it described as a new rocket artillery system last week, while expressing frustration over the continuance of U.S.-South Korea drills it sees as an invasion rehearsal and also the slow pace of nuclear negotiations with the United States.

North Korea had said it will wait to see if the August exercises actually take place to decide on the fate of its diplomacy with the United States and also whether to continue its unilateral suspension of nuclear and long-range missile tests, which leader Kim Jong Un announced last year amid a diplomatic outreach to Washington.

The allies have scaled down their major military exercises and also stopped regional dispatches of U.S. strategic assets such as long-range bombers and aircraft carriers since the first summit between Kim and President Donald Trump in Singapore in June last year to create space for diplomacy.

The North insists even the downsized drills violate agreements between Kim and Trump, who in Singapore vowed to improve bilateral ties and issued a vague statement on a nuclear-free Korean Peninsula without describing when and how it would occur.

Nuclear negotiations have been on a standstill since the collapse of the second Trump-Kim summit in Vietnam in February over disagreements in exchanging sanctions relief and disarmament.

The North’s recent weapons tests, which also included a short-range ballistic missile test on July 25 it described as a “solemn warning” to South Korea over its planned military drills with the United States, have dampened the optimism that followed the third summit between Trump and Kim on June 30 at the inter-Korean border. The leaders agreed to resume working-level nuclear talks that stalled since February, but there have been no known meetings between the two sides since then.

(AP)