A top North Korean official has made a rare apology to South Korean reporters for restricting their coverage of a concert by South Korean musicians in Pyongyang, according to a pool report Monday.

Kim Yong-chol, a ranking Workers' Party official in charge of affairs with South Korea, visited South Korean reporters at a Pyongyang hotel and asked for their understanding for being denied access to a theater where the performance was held.

"We're obliged to help reporters from the South side engage in free coverage and convenient filming. It was wrong to hinder the free media coverage and filming," Kim was quoted as saying.

"Sunday's event was special, as Chairman (Kim Jong-un) attended it. I think there might have not been sufficient cooperation between the chairman's security guards and concert organizers," he said.

Kim offered an apology on behalf of North Korean authorities, saying that the restriction was not intentional.

Except for one camera reporter, South Korean journalists were denied access to the East Pyongyang Grand Theatre where the South's art troupe was holding the concert with North Korean leader Kim Jong-un in attendance.

They covered the performance by watching live footage on a TV in a dressing room.

The South Korean government said Monday that it strongly protested to North Korean authorities over the unexplained restriction of media coverage.

Kim Yong-chol, a top military general, is suspected of having masterminded North Korea's sinking of a South Korean warhip in March 2010. He visited the South last month as the chief of the North's high-level delegation to the closing ceremony of the PyeongChang Winter Olympics.

This rare and quick apology by a top North Korean official appears to reflect the recent rapprochement between the two Koreas created by the North's participation in the Olympics.

The concert involved 11 South Korean acts and is part of a two-concert series titled "Spring Comes."

The North's leader proposed to South Korean officials that the two Koreas hold more cultural events, suggesting it would be better to hold a concert in Seoul around fall under the title of "Autumn Comes," according to the pool report.(Yonhap)