SEOUL, South Korea — South Korean reporters visiting North Korea’s capital to cover a K-pop performance there received a surprise on Monday: an unusually graceful apology from a senior North Korean official.

The official, Kim Yong-chol, a vice chairman of the North’s ruling Workers’ Party, visited the reporters’ hotel and apologized for their having been denied entry to a theater in Pyongyang, the capital, where the North’s leader, Kim Jong-un, watched South Korean musicians perform Sunday evening.

“We invited you and we are obliged to guarantee free coverage,” Kim Yong-chol was quoted in the reporters’ dispatches from Pyongyang as saying. “On behalf of the North’s authorities, I offer an apology and ask for your understanding for the wrong committed.”

It is extremely rare for North Korea to offer such a public apology to the South, or, for that matter, to apologize for anything. The rare gesture from a senior official reflected the North’s efforts to work toward a political détente on the Korean Peninsula that Kim Jong-un helped start in February by sending a delegation to the Winter Olympics in Pyeongchang, South Korea.