The exercise will involve more than 230 warplanes from both sides, including those stationed abroad, and around 12,000 personnel.

They include six F-22 Raptors and six F-35As. It's quite unusual for the US to deploy such advanced jets in the country.

Also to be mobilized are six EA-18G Growler electronic warfare jets and dozens of F-15C and F-16 fighter jets.

Some Marine F-35Bs, stationed in Japan, are also expected to take part in the training exercise to be joined by South Korea's F-15K, KF-16 and F-5 fighters, as well as other planes.

The two sides will focus on simulated precision airstrikes on mock North Korean nuclear and missile targets and transporter erector launchers that move missiles.

The Vigilant Ace drill is the allies' biannual training event.

"The realistic air combat exercise is designed to enhance interoperability between US and Republic of Korea forces and increase the combat effectiveness of both nations," the US

Seventh Air Force said in a press release. "VIGILANT ACE 18 highlights the longstanding military partnership, commitment and enduring friendship between the two nations. It is designed to ensure peace and security on the Korean Peninsula and reaffirms the US commitment to stability in the Northeast Asia region."

North Korea's foreign ministry issued a statement condemning the allies for planning to conduct what it described as their largest-ever joint aerial drill against its regime.

"The drill would be unprecedented in its size and nature of simulating actual combat situation as well as in the number of the US major strategic assets including F-22 Raptor and F-35 stealth fighters to be involved," the ministry said Saturday in the English-language document released by Pyongyang's media.

"The (Donald) Trump team is begging for nuclear war by staging an extremely dangerous nuclear gamble on the Korean peninsula," it added. "The international community terms the moves of the US

very alarming and is keeping a close watch on them with great concern and anxiety as the US is engrossed in making successive military provocations mobilizing greater amount of its nuclear strategic assets than ever, thereby driving the situation of the Korean peninsula to the brink of crisis."

It claimed that Washington's campaign to "demonize" Pyongyang can be regarded as a prelude to nuclear war, saying the communist nation is just engaged in "legitimate and righteous" measures to strengthen its self-defensive nuclear deterrence.

The North has long labeled regular South Korea-US military exercises as a rehearsal for invasion. (Yonhap)