North Korea warns US over nuclear submarine in South

North Korea on Tuesday condemned the arrival of a US Navy nuclear submarine in South Korea, saying that it will use "any defense means" to protect itself, according to the state-run media.

In a statement, the Defense Ministry called the deployment a "concentrated expression of the US' unchangeable madness toward North Korea."

"We express grave concern over the dangerous hostile military actions of the United States that could push the acute military standoff on the Korean Peninsula into an actual armed conflict," the statement said, urging Washington to halt "provocative acts that lead to further instability."

This came a day after the USS Alexandria, a Los Angeles-class attack submarine, arrived in the South Korean port city of Busan for resupply and crew rest. It marked the first US nuclear submarine visit to the peninsula this year.

Pyongyang said its armed forces are closely monitoring US military movements and are prepared to take any necessary measures to safeguard national security.

"We will not back down an inch from our confrontation with this tyrannical enemy," the statement said.

On Saturday, North Korean leader Kim Jong-un reaffirmed his commitment to expanding the country's nuclear forces, accusing the US of fueling global conflicts.

"The US stands unfailingly behind the world's big and small disputes and tragedies of bloodshed," Kim said, adding that this justifies Pyongyang's pursuit of "unlimited defense capability."

His remarks followed recent comments by President Donald Trump suggesting that Washington would maintain relations with North Korea.