PSA Group’s proposal to buy General Motors’s Opel brand quickly ran into a potential hurdle in Germany, with politicians and labor leaders vowing to protect jobs and the unit’s manufacturing footprint.

“The company carries responsibility for the sites, the development center and the securing of employment,” German Economy Minister Brigitte Zypries, a Social Democrat, said in an emailed statement to Bloomberg on Tuesday. “This is my clear expectation regarding General Motors.”

Zypries called it “unacceptable” that GM discussed a possible Opel sale without first speaking with the works council, labor unions and the state government in Hesse, where Opel is based. The manufacturer has two plants in Germany and the future of jobs at the sites could become a topic in this year’s federal election.

A combination would create a manufacturer with about 16 percent of the European car market, pushing past Renault to become the region’s second-biggest auto group after Volkswagen. A deal would also be the second run at linking the two mass-market carmakers. Any renewed effort is likely to center on finding ways to cut costs – and ultimately jobs – because the two have overlapping product offerings.

Hesse’s Economy Minister Tarek Al-Wazir said the carmaker’s employees must get swift clarity about the future of the Opel sites. Opel has been on an upward track in recent years and his government will work to keep it this way.