SEOUL, Korea, Republic Of - South Korea said Tuesday that a joint military exercise scheduled with the U.S. has been suspended to support ongoing talks both countries have with North Korea.

"South Korea and the U.S. made the decision as we believe this will contribute to maintaining such momentum," said Choi Hyun-soo, a Defence Ministry spokeswoman.

She spoke after the U.S. and South Korea announced that the Ulchi Freedom Guardian drills slated for August had been called off.

The announcement was widely anticipated following President Donald Trump's meeting with North Korean leader Kim Jong Un last week. Trump said after the summit in Singapore that he would suspend the U.S. military's "war games" with South Korea unless and until the talks on ending North Korea's nuclear weapons program break down.

His statement appeared to catch both South Korea and the Pentagon by surprise, but they presented a united front in cancelling the upcoming exercise.

Dana White, spokeswoman for the U.S. Defence Department, said planning for the summer drills had stopped, but no decisions have been made on any other military exercises with South Korea. Joint exercises with Japan and other countries in the Pacific will continue.

Choi echoed that nothing has been decided on other exercises.

Japanese Defence Minister Itsunori Onodera showed understanding for the move but stressed the need for the two countries to continue their other joint drills.

He called U.S.-South Korean exercises "important pillars" to maintaining regional peace and stability. Plans for U.S.-Japan exercises are unchanged, he added.

Last year's Ulchi Freedom Guardian went on for 11 days in August and involved about 17,500 U.S. and 50,000 South Korean troops. Also participating were other nations that contributed forces during the 1950-53 Korean War, including Australia, Britain, Canada and Colombia.

The other major U.S. exercises with South Korea - Key Resolve and Foal Eagle - took place earlier this spring. They historically include live-fire drills with tanks, aircraft and warships and feature about 10,000 American and 200,000 Korean troops. The drills were delayed this year because of North Korean participation in the Winter Olympics in South Korea in February.