North Korean soldiers carry packs marked with the nuclear symbol as they parade during a ceremony in July. (Wong Maye-E/AP)

South Korea said Thursday it would resume broadcasting messages into North Korea over powerful loudspeakers, part of an effort to punish Kim Jong Un’s regime for this week’s nuclear test.

After a wave of global condemnations and emergency meetings, the international community searched for ways to escalate pressure on North Korea for its latest nuclear test.

Pyongyang claimed Wednesday that its test that day

involved a hydrogen bomb, which would mark a huge leap in the North’s nuclear capabilities. But experts say it appeared to be a less powerful atomic device similar to ones the North have detonated on three previous occasions since 2006.

Despite the international outrage, there appeared to be few good options for inflicting deeper pain on a regime that has withstood almost a decade of increasingly severe sanctions.

South Korea said it would resume a practice that proved surprisingly effective over the summer: blasting messages critical of Kim as well as a playlist of the South’s signature K-pop music into North Korea, the world’s most isolated state.

It will turn on the banks of speakers lined up along the demilitarized zone separating the two Koreas at noon local time on Friday, said Cho Tae-yong, one of South Korean President Park Geun-hye’s national security advisers.

This week's nuclear test was “a grave violation” of an inter-Korean deal struck in August, Cho said, according to the Yonhap News Agency.

A series of incidents in the summer had the North threatening war and the South vowing to retaliate, but the standoff ended after marathon talks. Under the deal that was struck, Pyongyang expressed regret for an attack that severely injured two South Korean soldiers and Seoul agreed to turn off the speakers.

Huge banks of 48 speakers had been blasting messages about 12 miles into North Korea at night and about half that distance during the day.

“Kim Jong Un’s incompetent regime is trying to deceive the world with its lame lies,” a kind-sounding woman would say in one of the messages in a slow, deliberate voice. In North Korea, the Kims are revered as near-deities.

Although Seoul agreed to turn off the loudspeakers, it refused to dismantle them, saying it would leave them up in case of future Northern transgressions.

Cho said South Korean troops remained in a combat-ready position and would respond to any North Korean provocations.

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