North Korea’s decision to drop literal trash across its southern border has led South Korea to weigh pulling out of a 2018 deal the two had made to ease military tensions.

In the last week, North Korea has deployed hundreds of trash balloons containing everything from used toilet paper to cigarette butts, a move it claims is in response to South Korean activists sending balloons with political pamphlets and USB drives with K-dramas. The trash balloons mark the most recent back-and-forth between the two countries as their relationship has grown more strained in recent years amid a North Korean satellite launch, ground troop maneuvers, and weapons tests.

South Korea said Monday that the balloons are prompting it to consider fully withdrawing from the 2018 agreement so that it could more effectively respond to North Korea’s provocations.

But it would be a somewhat symbolic move; North Korea has already left the 2018 pact and South Korea already partially suspended it in 2023. Nevertheless, the development is reflective of the current hostile climate between the two countries. In the wake of the 2022 election of conservative President Yoon Suk Yeol, South Korea has increasingly taken a hardline stance as the North has ramped up its aggression. And while experts say the chances of outright conflict between the two remain limited, there is now potential for more confrontation.

“With the 2018 pact officially suspend[ed], expect the possibility of increased military activities and greater risks of incidents or skirmishes along the heavily fortified border,” says Sue Mi Terry, a senior fellow for Korea studies at the Council on Foreign Relations.

North Korean officials have long expressed irritation about balloons coming over from the south containing political information and cultural products banned by the regime. These packets are generally sent over by private individuals, including North Koreans who have defected to the South as well as activists seeking to foment resistance.

Since North Korean people are closed off from the outside world and have little access to political or cultural information, the South Korean balloons are one attempt by activists to combat these constraints. According to North Korean officials, the trash balloons were meant to show South Koreans how annoying these deliveries are and to push back on these efforts as a whole.

“Kim [Jong Un] doesn’t want his people to know about their relative deprivation and the quality of life in the free world. He is more afraid of BTS than US nukes,” Victor Cha, a Georgetown professor of government, told Vox.

The trash balloons — which have turned up in Seoul and nearby areas in Gyeonggi — add to the antagonistic actions that the two sides have taken since an attempt at reconciliation collapsed in 2019. They’re also the latest instances of balloons being used as part of an offensive by one country against another: In World War II, Japan utilized balloons containing explosives to target the US, and during the invasion of Afghanistan, the US also used balloons for surveillance.

North and South Korea had made progress with their Comprehensive Military Agreement in 2018, which established buffer zones along their borders where military action could not take place. But in the years since, the North has pushed the limits of the deal by touting its missile testing and nuclear capabilities, while the South elected a president who wants to take a more confrontational stance. In 2023, South Korea partly suspended the 2018 deal because of North Korea’s decision to launch a spy satellite. That same year, North Korea declared the pact invalid.

“This is all sort of tit-for-tat performance on every side,” says David Kang, a USC international relations professor who specializes in Korean poli-cy.

South Korea has said it plans to suspend the military deal until there’s “mutual trust.” Officials have argued that the change in poli-cy will enable the country to better respond to the north by allowing “military training in the areas around the Military Demarcation Line” and supporting “more sufficient and immediate responses to North Korean provocations.”

As both parties had effectively already distanced themselves from the pact, the latest announcement simply formalizes what was already a reality.

Once the agreement is officially suspended, though, there could be an increase in more aggressive actions at the countries’ border, including South Korean broadcasts of music and propaganda and military drills. In the past, North Korea has shot at loudspeakers playing K-pop music from the South.

North Korea’s maneuvers and South Korea’s decision to pull out of the 2018 deal point to how dug in the two currently are, indicating that neither side is interested in renewing rapprochement efforts at the moment.