South Korean President Yoon Suk Yeol’s approval rating slid to its lowest level since he took office as he tried to defend his declaration of martial law against a push to oust him via impeachment.

The support rate for Yoon fell to 11% in a weekly tracking poll released Friday by Gallup Korea, down 5% percentage points from last week’s survey.

The survey result was released after South Korea’s opposition bloc filed a second impeachment motion against Yoon on Thursday. The chances of its passage appear higher than the previous vote as more lawmakers from Yoon’s own People Power Party have indicated that they will support the impeachment.

The poll was conducted among 1,002 respondents across the country and had a margin of error of plus or minus 3.1 percentage points, Gallup Korea said.

Among those who had an unfavorable view of Yoon, 49% cited his declaration of martial law.

In the face of growing public anger over the failed martial law attempt last week, Yoon tried to justify his decision as he vowed to fight any case against him.

The opposition needs to secure 200 votes in parliament to pass the motion which they plan to report at a plenary session on Friday. The ballot is expected to take place on Saturday.

A successful motion would result in an immediate suspension of duties for Yoon and a Constitutional Court case lasting up to 180 days. If the court rules against the president, he would be forced out of office, triggering a presidential election within 60 days.