South Korea's president has expressed concern and frustration with North Korea's continuing threats.
In a speech Friday to graduating military cadets, President Park Geun-hye told them that she will "deal strongly with North Korea's provocations." She called the current security situation "very grave," a day after Pyongyang officials moved to void non-aggression pacts with South Korea and said a telephone hotline with Seoul would be severed
The threats came only hours after The United Nations Security Council voted unanimously Thursday on a resolution approving new sanctions, in response to the North's latest nuclear test, with the important backing of North Korea's historical ally, China.
Earlier Thursday, the North Korean Foreign Ministry threatened a preemptive nuclear strike on the United States. The ministry framed the threat as its "right to preemptive nuclear attack against the headquarters of the aggressor." It also said the "United States is about to ignite a nuclear war."
North Korea also has threatened to void the 1953 armistice that ended the Korean War, and it announced a series of military exercises to compete with drills being held by the U.S. and South Korean forces. Pyongyang has threatened five times since 1994 to scrap the armistice, but in each instance has stopped short of doing so.
The new U.N. sanctions strengthen maritime cargo inspections into and out of North Korea and ban certain luxury items from being shipped to the country. They also block any financial services or money transfers that could help the North's nuclear and missile programs, while tightening travel bans and adding new names to a blacklist of companies with links to North Korea's military.
The commander of U.S. Forces in South Korea, General James Thurman, also released a statement saying he is concerned about Pyongyang's threat -- warning he is ready to defend South Korea and "fully enforce the conditions of the armistice."
North Korea's rhetoric has become more heated following international condemnation of its February nuclear test and December missile launch.