Tensions in the Korean peninsula have escalated after North Korea reinstalled loudspeakers across the border, while activists in the South started sending propaganda-carrying balloons.
North Korea's military's move near the demilitarised zone (DMZ) defies inter-Korean peace agreements, with Seoul reiterating that Pyongyang would "have to pay for the consequences".
"We're also considering reinstalling our own loudspeakers," a spokeswoman at Seoul's defence ministry said. "But the North hasn't begun any broadcast yet, and we're just getting ready to be able to counteract at any time."
It comes after South Korean activists were seen sending propaganda-carrying balloons across the border into the North.
Relationship between the two neighbours have deteriorated in the recent weeks after the North blew up a joint liaison office, and threatened military action.