Korean President Yoon Suk-yeol makes an address at a dinner meeting with Koreans residing in Canada at a Toronto hotel, Sept. 22. Yonhap

President Yoon Suk-yeol's approval rating fell below 30 percent, a poll showed Friday, amid public criticism over his handling of diplomatic affairs in his ongoing three-nation trip.

In the poll of 1,000 adults conducted by Gallup Korea from Tuesday to Thursday, 28 percent positively assessed Yoon's job performance, down 5 percentage points from the previous week.

Yoon's disapproval rating jumped by 2 percentage points to 61 percent.

Yoon's approval rating slid below 30 percent just a week after it went back up above the threshold following a six-week streak in the 20 percent range in Gallup polls.

According to the pollster, many respondents cited the government's scrapping of a plan to build a new state guest house late last week and Yoon's handling of summit diplomacy, such as the cancellation of book-signing before the state funeral of Queen Elizabeth II, as reasons for disapproval.