South Korea’s unification ministry has welcomed a new amendment to the Aviation Safety Act banning all unmanned balloon flights in no-fly zones, saying the revision closes a loophole that allowed activists to launch balloons toward North Korea amid Seoul’s crackdown on leafleting.

“Since its launch, the Lee Jae Myung administration has taken proactive measures to ease military tensions and restore trust between the two Koreas …,” the ministry stated in a news release. “The revised Aviation Safety Act is expected to support these efforts.”

Under the current law, balloons carrying objects weighing less than two kilograms can be flown in