North Korea threatened Thursday to cancel the first reunion of families on the divided peninsula since 2010, amid joint South Korean and U.S. military drills.

The joint exercises are scheduled for later this month, and North Korea said a nuclear-capable B-52 bomber flew off the South’s coast on Wednesday, when both sides agreed to the reunion, Reuters reports.

“It does not make sense to carry out the reunion of families, who were separated due to the War, during a dangerous nuclear war practice,” a spokesman for the North Korean Policy Department of the National Defense Commission said Thursday, according to CNN.

The two countries had agreed Wednesday to allow 100 people separated by the 1950-53 war, most of them in their 80s and 90s, to meet in late February at a resort on the North Korean side of the border that used to be jointly operated by both sides.

A U.S. military spokeswoman told Reuters that she could not discuss specific missions but said: “The U.S. Pacific Command has maintained a rotational strategic bomber presence in the region for more than a decade.” A South Korean military official confirmed to the Yonhap news agency a training flight involving a single aircraft, according to Reuters.

North Korea pulled out of similar plans for a reunion in September, blaming the South for escalating tensions.

[Reuters]

Write to Noah Rayman at noah.rayman@time.com.