The Pacific Air Forces tweeted late Tuesday that U.S. airmen have arrived in Guam to work with Japan and South Korea to counter any threat posed by North Korea.

"S. Dakota #Airmen arrive on Guam; conduct #bilateral missions w/Japan & ROK — U.S. ready to #fighttonight," PACAF tweeted.

The training comes on the heels of continued North Korean saber rattling, and news that broke Tuesday that North Korea has the capacity to deliver a miniaturized nuclear warhead to parts of America. North Korea's military said it is mulling a strike against Guam, a U.S. territory that also serves as a U.S. military base.

That threat prompted President Trump to say the U.S. would deliver "fire and fury" to North Korea if it keeps on provoking the U.S.

Joint Base Pearl Harbor-Hickam in Hawaii said two U.S. Air Force B-1B bombers joined Japanese and South Korean forces in "sequenced bilateral missions" on Aug. 7.

The bombers flew from Guam into Japanese airspace, and then flew over the Korean Peninsula. They were joined by Japanese and South Korean air support.

It said this is the first mission for U.S. crews deployed from Ellsworth Air Force Base in South Dakota.

"Throughout the approximately 10-hour mission, the aircrews practiced intercept and formation training, enabling them to enhance their combined capabilities and tactical skills, while also strengthening the long standing military-to-military relationships in the Indo-Asia-Pacific region," the base said in a statement.

The base quoted a pilot as saying, "How we train is how we fight and the more we interface with our allies, the better prepared we are to fight tonight."