President Moon Jae-in's approval rating dropped sharply this week, a poll showed Friday, amid a controversy over a recent South Korea visit by a North Korean official suspected of masterminding a naval attack that killed more than 40 South Korean sailors.

In a weekly poll conducted by Gallup Korea, 64 percent of 1,008 adults surveyed said they approved of the way Moon managed state affairs, down 4 percentage points from a week earlier.

The latest reading marked the second-lowest figure since Moon took office in May 2017 after 63 percent registered in the first and second week of February amid a controversy over the government decision to form a single unified women's hockey team with the communist North for the PyeongChang Winter Olympic Games.

The on-week drop followed a recent visit by Kim Yong-chol, the North's point man on South Korea who is believed to have orchestrated a 2010 attack against the South Korean warship Cheonan that killed 46 young sailors.

Kim was here as the chief of an eight-member delegation to the closing ceremony of the PyeongChang Olympics, held Sunday.

The Seoul government defended its acceptance of Kim, saying there was no definite evidence of his involvement in the 2010 attack and that he is one of the most important policymakers on inter-Korean ties.

The two Koreas resumed their dialogue after a two-year hiatus in January to discuss the North's participation in the PyeongChang Olympics.

In his meeting with the South Korean president Sunday, the North Korean official said his country was also willing to hold bilateral dialogue with the United States, which Moon earlier called a prerequisite to resuming multilateral negotiations aimed at denuclearizing the North.

Still, the main opposition Liberty Korea Party reacted furiously against the North Korean official's visit, staging massive protest rallies and even demanding prosecution of the North Korean.

The Gallup survey showed LKP's approval rating gained 2 percentage points to 13 percent, while that of the ruling Democratic Party came to 44 percent, falling 4 percentage points from a week before.

The approval ratings of the minor opposition Bareunmirae Party and the progressive Justice Party remained unchanged at 8 percent and 6 percent, respectively.(Yonhap)