0732 GMT March 22, 2018
The drills come a week after North Korea said it had tested its most advanced intercontinental ballistic missile capable of reaching the United States as part of a weapons program that it has conducted in defiance of international sanctions and condemnation, Reuters wrote.
Chinese Foreign Minister Wang Yi said it was "regrettable" that all parties had not "grasped the window of opportunity" presented by two months of relative calm before the North's most recent test.
China and Russia had proposed that the United States and South Korea stop major military exercises in exchange for North Korea halting its weapons programs. Beijing formally calls the idea the “dual suspension” proposal.
The annual US-South Korean drill, called Vigilant Ace, will run until Friday, with six F-22 Raptor stealth fighters to be deployed among the more than 230 aircraft taking part.
North Korea's Committee for the Peaceful Reunification of the Country called US President Donald Trump "insane" on Sunday and said the drills would "push the already acute situation on the Korean peninsula to the brink of nuclear war".
F-35 fighters will also join the drills, which will include the largest number of 5th generation fighters ever to have taken part, according to a South Korea-based US Air Force spokesman.
Around 12,000 US service members, including from the Marines and Navy, will join South Korean troops. Aircraft taking part will be flown from eight US and South Korean military installations.
Trump said last week that additional major sanctions would be imposed on North Korea after Pyongyang's intercontinental ballistic missile test.
Earlier last month, Trump put North Korea back on a list of state sponsors of terrorism, a designation that allows the United States to impose more sanctions.
Russia has accused the United States of trying to provoke North Korean Leader Kim Jong-un into "flying off the handle" over his missile program to hand Washington a pretext to destroy his country.
Speaking at a news briefing in Beijing, Wang said China consistently opposed any behavior that elevated tensions.
"And measures that don't abide by or are outside the UN Security Council resolutions lack basis in international law and damage the rights of United Nations members," Wang said when asked about the prospect of further US sanctions against North Korea.
The North's KCNA state news agency, citing a foreign ministry spokesman, said on Saturday the Trump administration was "begging for nuclear war by staging an extremely dangerous nuclear gamble on the Korean peninsula".
North Korea has tested dozens of ballistic missiles and conducted its sixth and largest nuclear bomb test in September, in violation of UN Security Council resolutions.