Talks on forming a Czech government have been thrown into chaos after a front-runner to get the foreign minister job was engulfed in a scandal over social media comments.

The Motorists for Themselves (Motoristé sobě) party threatened to walk away from negotiations with the right-wing populist ANO, of likely next prime minister Andrej Babiš, and the far-right Freedom and Direct Democracy (SPD) over the issue.

The Czech news outlet Deník N over the weekend reported that Filip Turek of the Motorists party — a former member of the European Parliament, racing driver and candidate to be foreign minister — had made racist, sexist and homophobic comments on Facebook before entering politics. Turek denied being behind the posts in a video posted on Facebook.

“I absolutely reject the idea that I would have created something like that, written it, or even had such a thought. This has crossed all boundaries,” Turek said in the video.

Police are now investigating the posts, and the Motorists said they are filing a criminal complaint against Deník N.

Motorists’ party chairman Petr Macinka on Monday threatened to blow up the ongoing coalition talks. “I’m not looking for a replacement for Filip Turek,” Macinka said on Sunday on Czech TV program “Otázky Václava Moravce”. `”Either we’ll be in the government, or we’ll be in the opposition — there is no third option.”

Romea, an organization that works on behalf of the Roma community, started a petition urging ANO chairman Babiš and Czech President Petr Pavel not to nominate Turek as a Cabinet minister.

Pavel, who will have to officially appoint the ministers, said that if the authenticity of the posts is confirmed, it would be “a major problem.”

Turek has been embroiled in several scandals since he entered politics and won a seat in the European Parliament last year. He has been investigated over an image that appeared to show him making a Nazi salute and also over allegations by his ex-girlfriend, who accused him of rape and abuse. Turek denied all the allegations, calling them “absurd.”

Babiš, who secured a decisive victory in the Czech election earlier this month, aims to form a government with the support of the SPD and the Motorists. Without the Motorists’ backing, he would lack a majority in parliament, unless parties that previously refused to cooperate with him reconsider their position.

He plans to meet both Turek and Macinka later Monday.