South Korea and the United States launched a major air force exercise Monday, with two dozen U.S. stealth jets mobilized, a move that was denounced by the North for bringing the region to the "brink of nuclear war.”

The five-day Vigilant ACE (air combat exercise) comes less than a week after North Korea fired a new intercontinental ballistic missile (ICBM), dubbed the Hwasong-15, and announced the completion of its "nuclear force." The drill is considered the largest-ever combined air force drill between the allies, involving more than 230 warplanes including U.S. F-22 Raptor stealth fighter jets, South Korean F-15K, KF-16 and F-5 fighters and around 12,000 U.S. military personnel.

The air maneuvers will simulate strikes on "mock North Korean nuclear and missile targets and transporter erector launchers that move the North's missiles," the South Korean Air Force told Yonhap News Agency on Sunday.

This is the first time that the U.S. has deployed six F-22 at one time in the Korean peninsula. Six F-35As and a dozen F-35Bs, operated by the U.S. Marine Corps, will also take part in the training, which will continue till Thursday. Other assets from both the allies include two B-1B Lancer bombers, six EA-18G Growler electronic warfare jets, and dozens of F-15C and F-16 fighter jets. South Korea has fielded F-15K, KF-16, FA-50 and F-5 fighters, as well as other planes.

"It's aimed at enhancing the all-weather, day and night combined air power operation capabilities of South Korea and the U.S. They will conduct the drills in various wartime scenarios including simulated precision strikes on the mock North Korean missile targets," South Korea's defense ministry said. 

The U.S. 7th Air Force said, "The realistic air combat exercise is designed to enhance interoperability between U.S. and Republic of Korea forces, and increase the combat effectiveness of both nations."

The air combat exercise comes after last week's test-launch by North Korea of its most powerful intercontinental ballistic missile (ICBM), Hwasong-15, although the U.S.-South Korea drills was already been planned earlier. The Hwasong-15 ICBM could theoretically travel about 13,000 km and the North claimed it was far enough to hit anywhere in the mainland U.S.

North Korea reacted angrily Sunday to the air drills that are being conducted, accusing the U.S. and South Korea of a "grave military provocation" that will "push the already acute situation on the Korean Peninsula to the brink of nuclear war."

"What matters is the fact that the drill simulating an actual war is to be staged at a time when insane President Trump is running wild," a commentary carried by the official Korean Central News Agency said. "The situation clearly proves that the U.S. and South Korean puppet war maniacs are just aggressors and provocateurs breaking peace and stability on the Korean Peninsula," it added.

Also, National Security Adviser H.R. McMaster on Sunday said Trump was prepared to "take care" of the North's weapons programs, however he didn't specify how. "If necessary, the president and the United States will have to take care of it because he has said he's not going to allow this murderous, rogue regime to threaten the U.S. with the most destructive weapons on the planet," McMaster told Fox News Sunday.