She had reportedly suffered from an illness for a long time and had been in critical condition in recent days.

Moon plans to hold a "calm" family funeral at the wishes of the deceased, according to Cheong Wa Dae spokesperson, Ko Min-jung.

No condolence calls or flowers will be accepted, she added. Ko asked the public to convey mourning messages instead "with their hearts."

The president and first lady Kim Jung-sook were apparently present at the time of her death.

It's the first time in modern South Korean history that a sitting South Korean president's parent has died.

Earlier Tuesday, the president hurriedly visited her at the hospital right after attending a conference of Saemaeul Undong, or new community movement, leaders in Suwon, Gyeonggi Province.

Kang is survived by Moon and another son, as well as three daughters.

She will be laid to rest following a three-day private mourning period, a Cheong Wa Dae official told reporters.

While taking a special leave, the president will receive real-time briefings in case of an emergency in state affairs, the official added. He's expected to return to work later this week.

In his 2011 memoir, titled "The Destiny," Moon gave a detailed account of stories related to his parents, both born in Hungnam, South Hamgyong Province, which is now in North Korea.

His father, Moon Yong-hyong, and mother were refugees who fled the 1950 Chosin Reservoir battle to South Korea aboard the US ship the SS Meredith Victory.

About two years later, Moon was born. In his childhood, the father's business faltered and the mother earned a living through street vending or coal briquette delivery. Moon's father died of heart failure in 1978.

(Yonhap)