SEOUL (Yonhap) — North Korea threatened on Monday to target the United States with its nuclear weapons, saying its front-line targets include the Pacific Ocean, not just South Korea.

The communist party’s official newspaper, the Rodong Sinmun, said the North is ready to conduct nuclear attacks on U.S. soil.

“North Korean leader Kim Jong-un’s resolute determination is to defeat the U.S. on its own soil,” the newspaper said. “Our punishment will be the demise of the U.S.”

The North’s threat came amid concerns that Pyongyang has advanced its nuclear capabilities, raising tension in the region.

U.S. Forces Korea Commander Curtis Scaparrotti said in mid-April that he assumes the communist nation has the ability to deliver a ballistic missile with a nuclear warhead, but the North falls short of actually firing it as it has not yet been tested.

The North’s road-mobile KN-08, though untested, is believed to have a range of at least 5,500 km, which puts Alaska at risk, according to U.S. officials.

North Korea has been under heavy sanctions by the United Nations Security Council for three nuclear tests in 2006, 2009 and 2013 and multiple missile launches.