People observe a statue symbolizing women forced into wartime Japanese military brothels in front of the Japanese Embassy in Seoul on Sunday. AHN YOUNG-JOON/AP

A South Korean Buddhist monk is in critical condition after setting himself on fire to protest the country's settlement with Japan on compensation for wartime sex slaves, officials said Sunday.

The 64-year-old monk had third-degree burns across his body and serious damage to vital organs. He's unconscious and unable to breathe on his own, said an official from the Seoul National University Hospital, who didn't want to be named, citing office rules.

The man set himself ablaze late Saturday during a large rally in Seoul calling for the ouster of impeached President Park Geun-hye, police said. In his notebook, the man called Park a "traitor" over her government's 2015 agreement with Japan that sought to settle a long-standing row over South Korean women who were forced into sexual slavery by Japan's World War II military, police said.

Under the agreement, Japan pledged to fund a Seoul-based foundation that was set up to help support the victims. South Korea, in exchange, vowed to refrain from criticizing Japan over the issue and try to resolve the Japanese grievance over a bronze statue representing wartime sex slaves in front of its embassy in Seoul.

The agreement failed to bring closure to the emotional issue. The deal continues to be criticized in South Korea because it was reached without approval from victims, and students have been holding sit-in protests next to the Seoul statue for more than a year..

At the time of the deal, Seoul said there were 46 surviving South Korean victims.