Three German parties agreed Tuesday to form a center-left-led coalition government in a northeastern state, keeping the AfD out of power despite the far-right party having topped regional polls. 

The state election in Mecklenburg-Western Pomerania poll – a coastal area which used to be part of East Germany – was one of three regional elections in September in which Chancellor Friedrich Merz's ruling conservatives performed abysmally, fueling speculation his own party may seek to oust him.

The anti-immigration AfD came first with 38% of the vote in the state, winning 32 seats – not far short of an overall majority in the 71-member parliament. Merz's CDU party, by contrast, scored its worst-ever election result, failing to hit the 5% electoral threshold and thereby losing all its seats.

After several weeks of talks, the second- third- and fourth-placed parties – respectively the center-left SPD, the Greens and far-left Die Linke – announced they had struck a deal to form a 39-seat coalition government to lead the state.

"The negotiations were tough, and mostly ran late into the night," State Premier Manuela Schwesig reportedly said, as she announced the agreement in state capital Schwerin. 

Germany's mainstream political parties have long maintained a so-called "firewall" policy that aims to keep the far right out of power, in a country still haunted by its Nazi past. 

But the AfD hopes to soon form its first regional government, in Saxony-Anhalt, another part of the former East Germany, after winning 44% of the vote there in September.

Despite the defeats in the regional polls, Merz has vowed not to quit and insisted he would keep his ruling coalition together for the sake of Germany's "democratic future". 

His CDU governs in coalition with the SPD at the national level, where the AfD has a clear polling lead for more than six months. The next national election could be as late as March 2029.