North Korea's Kim Yo Jong warns US against 'foolish act' that risks security

SEOUL (Reuters) -North Korea's Kim Yo Jong, sister of leader Kim Jong Un, said on Monday that the United States should avoid any "foolish act" that could put its security at risk and rejected offers of talks as a ploy, state news agency KCNA reported.

Kim made her comments after White House national security adviser Jake Sullivan said the United States remained concerned that North Korea would carry out another intercontinental ballistic missile (ICBM) test, after it last week fired an ICBM off its east coast.

"The U.S. should stop its foolish act of provoking the DPRK even by imperilling its security," Kim said in a statement carried by KCNA. DPRK refers to the North's official name, the Democratic People's Republic of Korea.

She criticised U.S. plans for a nuclear-armed ballistic missile submarine to visit South Korea and said that such efforts to increase "extended deterrence" would only push Pyongyang further from the negotiating table.

Kim, a powerful ruling party official, also rejected U.S. calls for unconditional talks and said that Washington was wrong if it believed North Korea's disarmament was possible.

"It is a daydream for the U.S. to think that it can stop the advance of the DPRK and, furthermore, achieve irreversible disarmament through the interim suspension of joint military exercises, halt to the deployment of strategic assets and the reversible sanction relief," she said.

North Korea has in recent days accused American spy planes of flying over its exclusive economic zone, condemned a recent visit to South Korea by an American nuclear-powered cruise missile submarine, and vowed to take steps in reaction.

(Reporting by Heekyong Yang; Editing by Angus MacSwan, David Holmes and Mike Harrison)