US President Joe Biden has said that a nuclear attack by North Korea against the United States or its allies would be the end of Kim Jong-un's regime.
Mr Biden said it was "unacceptable and will result in the end of whatever regime that would take such an action."
Biden's comments come as he and South Korean President Yoon Suk Yeol are set to today sign an agreement that includes plans to have US nuclear-armed submarines dock in South Korea for the first time in more than 40 years.