South Korea has said it will restart anti-North Korean propaganda loudspeaker broadcasts in border areas in response to continuing campaigns to drop trash on the South with balloons.

Following a national security meeting, the South Korean presidential office said the loudspeakers will be installed and begin broadcasts in border areas on Sunday.

The move is certain to anger North Korea and potentially prompt it to take its own retaliatory military steps.

North Korea flew hundreds of trash-carrying balloons to South Korea over the weekend in its third such campaign since late May, the South’s military said.

The move came days after South Korean activists floated their own balloons to scatter propaganda leaflets in the North.

North Korea has sent more than 1,000 balloons to drop tons of trash and manure in retaliation against South Korean civilian leafletting campaigns, adding to tensions between the war-divided rivals amid a diplomatic stalemate over the North’s nuclear ambitions.

In response, South Korea suspended a 2018 tension-easing agreement with North Korea. The move allows the South to restart live-fire military exercises and anti-North Korean propaganda loudspeaker broadcasts in border areas.

South Korea’s Joint Chiefs of Staff said it detected the North launching around 330 balloons toward the South since Saturday night and about 80 were found in South Korean territory by Sunday morning.

The military said winds were blowing eastward on Saturday night, which possibly caused many balloons to float away from South Korean territory.

The South’s military said the balloons that did land dropped trash, including plastic and paper waste, but no hazardous substances were discovered.

The military, which has mobilised chemical rapid response and explosive clearance units to retrieve the balloons and materials, alerted the public to beware of falling objects and not to touch balloons found on the ground but report them to police or military authorities.

The North’s vice defence minister Kim Kang Il later said his country would stop the balloon campaign but threatened to resume it if South Korean activists sent leaflets again.

In defiance of the warning, a South Korean civilian group led by North Korean defector Park Sang-hak said it launched 10 balloons from a border town on Thursday carrying 200,000 anti-North Korean leaflets, USB sticks with K-pop songs and South Korean dramas and US dollar bills.

South Korean media reported another activist group also flew balloons with 200,000 propaganda leaflets toward North Korea on Friday.

South Korean officials called the North Korean trash balloon launches and other recent provocations as “absurd, irrational” and vowed strong retaliation.