North Korean leader Kim Jong Un's influential sister Kim Yo Jong on Monday said regret expressed by Seoul over a January drone incursion into the North as wise behaviour.

South Korean President Lee Jae Myung had earlier expressed regret to Pyongyang after a drone entered North Korea earlier this year, calling the act "irresponsible."

What did  Kim Yo Jong say?

"The ROK [South Korea] president personally expressed regret and talked about a measure for preventing recurrence. Our government appreciated it as very fortunate and wise behavior for its own sake," Kim Yo Jong said in a statement carried by the official Korean Central News Agency.  

Leader Kim considered it "a manifestation ‌of ​a frank and broad-minded man's attitude," she said. Kim Yo Jong regularly comments on Pyongyang's external policy stance believed to reflect the views of her brother.

Initially, Seoul had denied the role of the government in the drone incursion, which took place in January, and suggested it was the work of civilians. However, Lee said an investigation found that government officials had been involved in the incident.

In February, Pyongyang warned of a "terrible response" if it found more drones transgressing the airspace, which compelled Seoul to investigate the claims.

What did Lee say?

"Although it was ​not our government's intention, we express our regret to the ​North over the fact that unnecessary military tensions ​were ‌caused by the irresponsible and reckless actions of some individuals," Lee said during a cabinet meeting.

"It has been confirmed that a National Intelligence Service official and an active-duty soldier were involved," Lee said.

He added that South Korea's constitution bans private individuals from conducting acts that could "provoke the North."

"Such actions, even when deemed necessary for national strategy, must be approached with extreme caution," he said.

Lee has been trying to mend ties with Pyongyang, however, his repeated overtures have consistently been brushed off.

Lee's expression of regret comes after North Korean leader Kim Jong Un labeled Seoul the "most hostile state" in a policy address in March in which he vowed to "thoroughly reject and disregard it."

Edited by: Natalie Muller