Prime Minister Chung Sye-kyun called for the speedy initiation of an inter-Korean investigation into the recent shooting death of a South Korean official by North Korean troops.

During a local radio interview on Monday, Chung said the truth should be revealed as soon as possible so that the incident, which he said "poured cold water" on efforts to improve cross-border ties, doesn't aggravate tension.

Chung's remarks came a day after South Korea's presidential office proposed the joint investigation to the North.

The prime minister also called for the restoration of communication channels between the two sides, including their military hotline, saying that the two Koreas have no other choice but to foster peace through dialogue.

Regarding some conservative groups' planned anti-government rallies this weekend, Chung said the people's constitutional right to protest "isn't any more important than people's lives and safety."

On Sunday, Chung warned of a zero-tolerance policy against illegal demonstrations on National Foundation Day on Saturday as part of COVID-19 quarantine, saying the participants will be arrested on sight.