Parliamentary confirmation hearings for President-elect Yoon Suk-yeol’s Cabinet picks are to kick off Monday, with Prime Minister nominee Han Duck-soo taking the stand for a two-day hearing.

The Democratic Party of Korea, which has vowed a tough vetting for all nominees, is likely to focus on Han’s career after he retired from the public sector. Prime minister is the only Cabinet post that requires parliamentary approval in South Korea.

Han’s hearing is to be followed by those for Interior Minister nominee Lee Sang-min and Defense Minister nominee Lee Jong-sup on Thursday. Culture Minister nominee Park Bo-gyoon is scheduled to appear for his confirmation hearing on the day after.

On May 2, confirmation hearings are set for Finance Minister nominee Rep. Choo Kyung-ho, Foreign Minister nominee Rep. Park Jin and Land Minister nominee Won Hee-ryong. Their hearings will be followed by checks on Health Minister nominee Chung Ho-young on May 3 and Unification Minister nominee Rep. Kwon Young-se on May 4.

The Democratic Party, which controls 170 out of 300 legislative seats at the National Assembly, has warned of tough hearings for Yoon’s Cabinet nominees, warning to drive Yoon and his aides to drop some of the nominations based on the nominees’ troublesome records and controversies from the past.

It was expected that Yoon and the People Power Party would have to give up some of their nominations in order to gain official approval of Han from the opposition Democratic Party-controlled parliament.

The liberal Democratic Party has set Health Minister nominee Chung as the first target of grilling during the hearing season besides Han.

Chung, a former chief of Kyungpook National University Hospital, faces allegations of abusing his authority to help his son and daughter gain admission to the institution’s medical school and exempt his son from military service.

Schedules for confirmation hearings of 10 other minister nominees are not set for the time being, but political sources said they expect their hearing schedules to be fixed and announced within the next few days.

Confirmation hearings for some of the remaining nominees are also expected to undergo rough terrain and serve as a hindrance to Yoon’s hopes for a successful start to his administration on May 10.

The Democratic Party is also preparing a fierce grilling of Justice Minister nominee Han Dong-hoon in particular. Han is a senior prosecutor and one of the closest confidantes of Yoon. His nomination itself stirred a controversy upon its announcement.

Han Dong-hoon, whose confirmation hearing schedule has yet to be decided, has been seen by many as a symbol of Yoon’s resistance to prosecution reform. Han is also seen as a prospective Cabinet member who will help Yoon maintain relations with investigative entities.

Education Minister nominee Kim In-chul also faces an allegation of giving himself approval to serve as an outside director for a private firm while serving as the president of the Hankuk University of Foreign Studies.