President Yoon Suk-yeol presides over a government-civilian meeting on national safety regulations at the presidential office in Seoul, Nov. 7. Yonhap

President Yoon Suk-yeol apologized to the nation Monday for the deadly Itaewon crowd crush, saying he will ensure a thorough investigation into the tragedy and hold those responsible to account.

Yoon issued the apology during a meeting held to review crowd control and other safety regulations in the wake of the tragedy that killed 156 people on Oct. 29.

"I dare not compare myself to the parents who lost their sons and daughters, but as the president who should protect the people's lives and safety, I grieve and my heart is heavy," he said. "I am apologetic and sorry to the bereaved families who are facing an indescribable tragedy and to nation that is sharing in the pain and sadness."

The remark was seen as his first formal apology to the nation, though he previously apologized in remarks during Buddhist and Christian memorial services.