SEOUL — North Korea cut off the last remaining military hotlines with South Korea on Wednesday, accusing President Park Geun-hye of South Korea of pursuing the same hard-line policy of her predecessor that the North blamed for a prolonged chill in inter-Korean relations.
Amid tensions over the North’s third nuclear test last month and ensuing UN sanctions, North Korea had already shut down Red Cross hotlines with South Korea and a communication line with the US military command in South Korea.
But its decision to cut off military hotlines with South Korea was taken more seriously in Seoul because the two Koreas have used those four telephone lines to control daily cross-border traffic of workers and cargo traveling to the North Korean border town of Kaesong.
The two countries run a joint industrial park at Kaesong, the last symbol of inter-Korean cooperation that has survived the political tensions of recent years. Seoul officials said 887 South Korean workers were in Kaesong on Wednesday.
The traffic was running normally Wednesday, South Korean officials said, indicating that the North Korean military did not go so far as to stop cross-border economic exchanges.
‘‘There do not exist any dialogue channel and communications means between the DPRK and the US and between the North and the South,’’ said a North Korean statement sent to the South Korean military by telephone and later carried by the North’s official Korean Central News Agency. ‘‘Not words but only arms will work on the US and the South Korean puppet forces.’’
DPRK stands for the Democratic People’s Republic of Korea, the North’s official name.
The North’s action came a day after its top military command ordered all its missile and artillery units to be on ‘‘the highest alert’’ and ready to strike the United States and South Korea.
It also vowed to take ‘‘substantial military actions’’ to retaliate against joint US-South Korean military drills, which involved US B-52 bomber sorties over South Korea.
The last time North Korea severed all military hotlines, during joint US-South Korean military drills in 2009, it allowed an inter-Korean economic liaison office in Kaesong to serve as a communication channel with Seoul, and South Korean workers could commute to Kaesong.
The two Koreas continue to maintain hotlines between their civil aviation authorities.
“Under the situation where a war may break out any moment, there is no need to keep North-South military communications,’’ the North said Wednesday.
The North Korean action came shortly after South Korea’s president stressed both firmness and reciprocity in North Korea policy.
‘‘If North Korea provokes or does things that harm peace, we must make sure that it gets nothing, but will pay the price, while if it keeps its promises, the South should do the same,’’ Park said during a briefing from her government’s top diplomats and North Korea policy makers.
‘‘Without rushing and in the same way we would lay one brick after another, we must develop South-North relations step by step, based on trust, and create sustainable peace,’’ she said.
Her new unification minister, Ryoo Kihl-jae, South Korea’s point man on North Korea, later told reporters that his government was willing to consider lifting trade embargoes imposed on the North after the deadly sinking of a South Korean navy ship in 2010 — but not before North Korea takes responsibility for the sinking, which killed 46 South Korean sailors.