Update at 1935 KST: This article has been updated to reflect the MND’s retraction of its claim that the exercise was the “largest” to take place on the Korean peninsula.

Washington and Seoul on Monday kicked off a major air combat exercise that North Korea has described as the “largest ever.”

The Republic of Korea Air Force (ROKAF) Operations Command and the Seventh Air Force will conduct the annual exercise named “Vigilant Ace” until Friday, South Korean Ministry of National Defense (MND) announced on Monday.

Moon Sang-gyun, a defense ministry spokesperson, said the purpose of the joint air combat drill