SEOUL, South Korea (AP) — North Korea has warned the United States will face a very grave situation because President Joe Biden made a big blunder in his recent speech by calling the North a security threat and revealing his intent to maintain a hostile policy against it. Last week, Biden, in his first address to Congress, called North Korea and Iran’s nuclear programs serious threats to America’s security and world security, and said he’ll work with allies to address those problems through diplomacy and stern deterrence. A senior Foreign Ministry official says North Korea will be compelled to respond with corresponding measures. The White House said Biden plans to veer from the approaches of his two most recent predecessors as he tries to stop North Korea’s nuclear program.