Armin Laschet, the leader of Germany's ailing Christian Democrats (CDU), will officially resign as state premier of North Rhine Westphalia on Monday.
Laschet, who was at one point the front-runner to succeed fellow conservative Angela Merkel as German chancellor, oversaw the CDU's worst ever showing in parliamentary elections on September 26.
The 60-year-old announced he would be standing down as state premier before the Bundestag elections, even if he didn't become Germany's next chancellor.
Laschet is due to remain acting state premier until he takes his seat as a member of the incoming German parliament, or Bundestag, in its inaugural session on Tuesday.
On Wednesday, North Rhine Westphalia Transport Minister Hendrik Wuest is expected to be elected the new state premier in a special session of the state parliament.
The 46-year-old was elected CDU state leader in North Rhine-Westphalia on Saturday.
With Laschet as its candidate for chancellor, the CDU and its Bavarian allies, the Christian Social Union (CSU), achieved a historically bad result in the Bundestag elections.
