Merz congratulates Greens after upset in key German state election

German Chancellor Friedrich Merz on Monday congratulated the Greens on their razor-thin victory over his Christian Democrats (CDU) in the state of Baden-Württemberg - an unexpected setback for the conservatives in the first of five regional votes this year.

Preliminary results from Sunday's election showed the Greens on 30.2%, ahead of the CDU on 29.7% - although the two parties are set to hold the same number of seats in the state parliament.

Merz's centre-right party had led in polls for months but fell behind at the last minute after a strong comeback by the Greens, whose lead candidate Cem Özdemir is expected to become the first German state premier of Turkish heritage.

The result left the parties all but certain to extend their coalition in the regional government in Stuttgart.

Both have ruled out collaborating with the far-right Alternative for Germany (AfD), who finished third on 18.8%, with Merz on Monday reiterating that "we will not work with this party."

Given that the top two parties drew level on seats in the Stuttgart parliament, Merz called for "balance" in the next coalition agreement and state government.

Jens Spahn, a senior conservative lawmaker and ally of Merz, suggested that the parties could share the leadership of the prosperous state.

The CDU's lead candidate in the election, Manuel Hagel, described the situation as a "stalemate," setting up a tricky phase of negotiations to form the next state government.

The conservative premier of neighbouring Bavaria, Markus Söder, blamed the upset on a "smear campaign" against Hagel, after an eight-year-old video went viral showing the lawmaker, then 29, delighting over a schoolgirl's "fawn-coloured eyes" during a classroom visit.

Following Sunday's surprise Green comeback, all attention turns to the state of Rhineland-Palatinate, where the Social Democrats - themselves picking up the pieces after a historically poor showing in Baden-Württemberg - are attempting to hold on to power in a head-to-head battle with the CDU ahead of the vote on March 22.