HONG KONG — The United States and South Korea began their largest combined air force drills Monday, with plans to carry out simulated strikes on North Korean nuclear and missile testing sites, South Korean military officials said.

Some 230 aircraft will take part in the drills, which will include some of the Pentagon’s most powerful warplanes, such as stealth F-35 Lightning II fighters and B1-B Lancer bombers. They come just a week after North Korea tested a missile that analysts said had the capability of reaching much of the continental United States.

The drills were part of an annual exercise that had been planned before North Korea conducted the missile test, officials said.

The exercise is “aimed at enhancing the all-weather, day and night combined air power operation capabilities of South Korea and the U.S.,” South Korea’s defence ministry said.

Such drills have drawn vigorous criticism from North Korea, whose state news media said Sunday that the latest exercises were pushing the Korean Peninsula “to the brink of nuclear war.” It warned that Pyongyang would “seriously consider” countermeasures against the drill and that the United States and South Korea would “pay dearly for their provocations,” the North’s Korean Central News Agency said.

Underscoring the tensions, Sen. Lindsey Graham of South Carolina urged the Pentagon on Sunday to move dependents of US service members out of South Korea because of the threat of conflict. More than 28,000 US troops are stationed there, many living with their families.

“It’s crazy to send spouses and children to South Korea, given the provocation of North Korea,” Graham, a member of the Senate Armed Services Committee, told CBS’s Face the Nation.

“I think it’s now time to start moving American dependents out of South Korea,” he added.

The military exercises that began Monday involve 12,000 personnel and also include six F-22 Raptors, representing the largest deployment of the stealth fighters to South Korea, officials said.

The drills will be conducted under wartime scenarios that include attacks on mock North Korean nuclear and missile targets, South Korea’s military said.

North Korea’s missile launch last Tuesday came after more than a two-month lull in the country’s nuclear and missile testing, which raised some hopes that it might be extending an olive branch to ease the hair-trigger military tensions on the peninsula.

Gerry Mullany/The New York Times