North Korea suggested the drills they will push the area to the "brink of war".
North Korea has warned nuclear war is now inevitable after the United States staged huge drills involving hundreds of advanced warplanes.The chilling prediction comes after two US B-1B nuke capable bombers were confirmed to be among aircraft staging large-scale aerial exercises near the hermit state. The president then announced the Wednesday after that he had already spoken to China's President Xi Jinping and that "major sanctions" would be imposed on North Korea.
People in a Chinese province bordering North Korea have been offered a nuclear survival guide by the local state-run newspaper.
B-1 flights represent the US's go-to response for North Korean provocations, such as missile tests, and the bomber flights draw a strong, sometimes dangerously escalating response from Pyongyang.
China, North Korea's neighbour and lone major ally, has again urged calm and says war is not the answer as Pyongyang said military drills involving the US and South Korean forces made war "an established fact".
However, US stealth jets did not join Thursday's practice, said the official, who asked not to be named.
North Korea threatened Sunday that if the United States continues to conduct joint military operations with South Korea "nuclear war [may break out] at any moment", Sky News reported.
It did nothing to stop Pyongyang carrying out its biggest intercontinental ballistic missile test to date earlier this week, alongside claims that the weapon was capable of hitting the U.S. mainland. The sortie prompted Pyongyang's foreign minister to warn that United States bombers could be shot down even if they did not enter North Korean airspace.
"B-1B bombers have been regularly dispatched to the Korean peninsula over the past years; however, it seems that the US Air Force might have enhanced its training to better prepare for actual warfare", he said.
Yang Uk, a senior fellow at the Korea Defence and Security Forum, said B-1Bs would be key to any strike targeting major North Korean facilities.
Washington has said it remains open to talks if North Korea demonstrates it is serious about giving up its nuclear weapons but that its recent activities showed it was not.
North Korea regularly threatens to destroy South Korea and the United States and says its weapons programmes are necessary to counter U.S. aggression.