Seoul, Sep 30 (IANS): Seoul on Wednesday expressed deep regret over Pyongyang denouncing South Korean President Park Geun-hye's speech at the United Nations and threatening to cancel reunion of families separated by the 1950-53 Korean War.

Pyongyang's Committee for the Peaceful Reunification of Korea on Tuesday criticised Park's appeal for reunification of the two Koreas through the help of the international community and warned that a proposed reunion of families separated by the Korean War was imperilled by the South Korean president's UN speech, Xinhua news agency reported.

During her speech at the UN General Assembly on Monday, Park said North Korea should drop its adherence to nuclear weapons and walk the path of economic development with reform and openness.

South Korea and North Korea have agreed to hold the family reunion event from October 20 to 26 in the scenic resort of Mount Kumgang in North Korea.

Seoul's unification ministry spokesman Jeong Joon-hee said it was highly regrettable for Pyongyang to talk of cancellation of the keenly-awaited event.

Jeong urged North Korea to sincerely implement the August 25 agreement.

Top military advisors to Park and North Korea leader Kim Jong-un met in August to de-escalate military tensions on the Korean peninsula, caused by landmine blasts and exchange of fires in border areas.

After marathon talks, the two sides agreed to withdraw military alert and hold an inter-governmental dialogue in Seoul or Pyongyang at an earliest possible date. They also agreed to hold the family reunion event.