Ruling party presidential candidate Lee Jae-myung and his main opposition rival Yoon Suk-yeol are in a dead heat at 35 percent support each, a poll showed Friday.

Lee of the liberal Democratic Party (DP) gained 1 percentage point from a Jan. 18-20 survey, while Yoon of the conservative People Power Party (PPP) gained 2 points, according to the Gallup Korea poll of 1,000 adults conducted from Tuesday to Thursday.

Ahn Cheol-soo, the presidential candidate of the minor opposition People's Party, was in third place with 15 percent, followed by Sim Sang-jeung of the minor progressive Justice Party with 4 percent.

The proportion of undecided voters dropped by 2 percentage points to 10 percent.

President Moon Jae-in received an approval rating of 42 percent and a disapproval rating of 51 percent.

The DP received 37 percent support, followed by the PPP at 35 percent, the People's Party at 7 percent and the Justice Party at 5 percent.

The survey had a margin of error of plus or minus 3.1 percentage points at a 95 percent confidence level. (Yonhap)