German politics is in uproar after an eastern state parliament backed a state premier with support of the far-right Alternative für Deutschland (AfD).

Wednesday’s vote in Thuringia was always going to be a high-stakes affair after last October’s poll left outgoing premier Bodo Ramelow, of the Left Party, without a parliamentary majority.

Instead of following Mr Ramelow’s wish to be re-elected as head of a minority government with the Social Democrats (SPD) and Greens, the parliamentary sitting in Erfurt took a very different, taboo-breaking turn.

MPs from the liberal Free Democrats (FDP) and Christian Democratic Union (CDU) joined forces to back local FDP leader Thomas Kemmerich. Crucial for his election, though, was the support of the AfD.

After two inconclusive rounds of voting, a third round – requiring a simple majority in the 90-seat parliament – saw Mr Kemmerich receive 45 votes and Mr Ramelow 44. No one voted in the third round for the AfD candidate, as the far-right MPs switched their allegiance to the FDP man.

The AfD, the second-largest party in the Thuringian state parliament, welcomed the result on Wednesday as a “political revolution”. Amid cries of “hypocrite” and “charlatan”, Mr Kemmerich struggled to be heard in his inaugural address, insisting that “fire walls to political extremes remain intact”.

Thomas Kemmerich, leader of the state branch of Thuringia’s Free Democratic Party (FDP) and newly elected prime minister of Thuringia. Photograph: Jens Schlueter/AFP via Getty

“Whoever voted for Kemmerich has voted for a fierce opponent of extremism, left and right, as well as fascism,” said the 54-year-old.

But his surprise election, with no political programme and no parliamentary majority, indicates uncertain times ahead. His FDP holds just five seats in the state parliament and is likely to form a minority coalition with the CDU, with 21 seats.

Uncertain influence

It remains to be seen how dependent the coalition will be on AfD support to govern. To date the CDU – and all other mainstream parties – have refused to co-operate at state or federal level with the far-right party.

In a charged post-vote atmosphere, a Left Party politician with a congratulatory bunch of flowers tossed them in disgust at Mr Kemmerich’s feet while the SPD and Greens vowed to avoid anyone elected with AfD votes.

“For me this shatters a taboo. The conservative parties have formed a coalition with a party led by a fascist,” said Dirk Adams, head of the local Green Party, referring to state AfD leader Björn Höcke.

Mr Höcke has achieved notoriety in Germany for a stream of provocative remarks, such as dismissing Berlin’s Holocaust memorial as a “disgrace”.

The vote in Thuringia, one of Germany’s smallest states, has triggered shockwaves throughout the country. Further north in Berlin, Social Democrat (SPD) co-leader Norbert Walter-Borjans attacked as “unforgivable” the strategy of FDP and CDU.

Media outlets wasted no time in attacking the result as a “disgrace” – and predicted a snap election rather than co-operation with the Thuringian AfD, under observation by domestic intelligence as a suspected right-wing extremist grouping.

“Kemmerich’s party cleared the 5 per cent hurdle by just 73 votes,” wrote Der Spiegel, “and now he’s state premier at the mercy of the AfD.”