South Korea is mulling over countermeasures to North Korea reinstalling propaganda loudspeakers along the inter-Korean border, about half of which had been removed under a 2018 summit agreement.

According to government sources on Tuesday, the North Korean military completed setting up the loudspeakers at some 20 locations inside the Demilitarized Zone(DMZ).

Pyongyang could install more, as it had previously operated around 40 loudspeakers.

The North is expected to resume propaganda broadcasts and send anti-Seoul leaflets south of the border upon approval from the ruling party's Central Military Commission.

South Korea's Defense Ministry said it is closely monitoring movement in the North and that it is "fully ready to immediately respond to various possibilities."

Seoul faces a predicament as restoring its own loudspeakers in countering Pyongyang's apparent push to resume psychological warfare would violate the agreement from the Panmunjeom Summit in April 2018.