North Korea missile
North Korean leader Kim Jong Un supervised a ballistic rocket launching drill of Hwasong artillery units of the Strategic Force of the KPA on the spot in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang, North Korea March 7, 2017. Reuters

The United States and South Korea were threatened with “merciless ultra-precision strikes” by Kim Jong Un’s North Korea Tuesday, prompting the countries’ military chiefs to discuss appropriate “response options.”

In a statement Tuesday, the U.S. and South Korean military chiefs said North Korea could carry out “provocative actions” in response to the Key Resolve/Foal Eagle exercise, the large-scale joint drills between the allies.

Read: North Korea Issues Another Nuclear Missile Threat To US, South Korea Over Joint Drills

“The chairmen recognized the possibility that North Korea could conduct provocative actions during the Key Resolve/Foal Eagle exercise, or in connection with North Korean major political events in April,” the office of Gen. Joseph Dunford, the chairman of the U.S. Joint Chiefs of Staff said, according to Reuters.

The countries kicked off their large-scale joint drills on March 1. USS Carl Vinson set to lead an aircraft carrier group, as well as units of the U.S. special operations forces — including the U.S. Navy SEAL Team Six that carried out the Osama Bin Laden mission, Army’s Rangers, Delta Force and Green Berets — are taking part in the joint exercise.

North Korea, however, said the drills were a direct threat to the country, warning U.S. and South Korea that if their actions attempted to infringe upon the sovereignty of the North, they will have to face the consequences.

“If they infringe on the DPRK's [Democratic People's Republic of Korea or North Korea] sovereignty and dignity even a bit, its army will launch merciless ultra-precision strikes from ground, air, sea and underwater,” North Korea’s state news agency KCNA said Tuesday.

The U.S. said it stands by its allies in Asia and has kicked off the deployment of an anti-missile defense system (THAAD) in South Korea. The defense system is in response to North Korea’s repeated ballistic missile test-fires, the most recent of which were carried out last week.