When his conservative South Korean party bowed to show remorse for ex-president Yoon Suk Yeol's disastrous martial law decree, Kim Moon-soo sat alone and resolute in symbolic non-apology. Kim offered his first apology "to the people suffering from the consequences of martial law" last month.

Both Lee and conservative Kim pledged change for a country deeply scarred by a shock martial law briefly imposed by former leader Yoon Suk Yeol.

South Korea’s liberal opposition candidate Lee Jae-myung was expected to win an early presidential election on Tuesday.