President Yoon Suk-yeol delivers an opening speech for the 2022 Boryeong Mud Festival at Daecheon Beach on South Korea's western coast, Saturday, in this photo provided by his office. Yonhap

President Yoon Suk-yeol renewed his commitment to promote the constitutional values of free democracy, human rights and rule of law as South Korea commemorates Constitution Day on Sunday.

"The constitutional values of free democracy, human rights and rule of law are the foundation of national unity, and the process of realizing such values leads to the road for prosperity and development," Yoon wrote on his Facebook account.

"I will safeguard the spirit of the Constitution together with the great people," he said.

Yoon recalled his visit to the southwestern city of Gwangju a year ago to look back on the spirit of the 1980 pro-democracy uprising, in which he said people fought to defend the constitutional values with their blood.

In May, Yoon and some 100 lawmakers from the ruling People Power Party traveled to Gwangju to pay their respects to the victims of the democracy movement during a ceremony marking its 42nd anniversary. (Yonhap)