The incoming first female head of Germany’s most powerful labor union IG Metall is warning Elon Musk about efforts to avoid unionization at his Tesla Inc. factory near Berlin.

“You need to be careful. The rules of the game are different here,” said Christiane Benner, who is set to take the helm of the union on Monday at its general assembly in Frankfurt.

The warning is a shot across the bow for Musk, whose factory churns out the popular Model Y — Europe’s best-selling car earlier this year — and has so far refused to sign the kind of wage agreements that are standard in Germany, putting the company on a collision course with Benner.

IG Metall has the power to initiate walkouts at some of Germany’s biggest firms, including Airbus, Siemens, Volkswagen and other titans of industry. Wage negotiations for its 3.9 million workers are closely watched by European Central Bank due to their potential impact on inflation.

While Tesla’s 12,000-employee plant is a key concern, Benner, speaking in an interview with Bloomberg News, outlined a broad set of worrying developments putting pressure on Germany’s workers.

Weaker demand from China, higher interest rates and the lingering fallout from last year’s energy crisis have already caused some factories to close and others to shift production abroad. The economy is forecast to shrink this year. At the same time, the transition to renewable energy and other emerging technologies are requiring workers to have new sets of skills.

“Things are very turbulent at the moment,” Benner said. “Re-qualification is going to be very important.”

Read more: German Industrial Production Shrinks for Fourth Month

IG Metall is Europe’s biggest manufacturing union, representing workers on automaker assembly lines, steelmaking mills and other factories. The organization takes in about €500 million in annual membership fees and has repeatedly caused stoppages at Germany’s most famous firms. With its vast membership, the organization holds considerable political clout.

Benner, 55, argues that German politicians have been too slow in tackling the country’s structural issues, putting at risk workers in industries like auto production, which employs roughly 800,000 people.

A growing number of auto-industry workers in and outside of Germany are demanding better pay and job security in the shift to electric vehicles. The United Auto Workers union has launched a major strike targeting General Motors, Ford and Stellantis in the US, halting output at several factories. The concern is that EVs, which require fewer moving parts and workers to make, will cost jobs and reduce wages.

Read more: UAW and GM Inch Toward Tentative Deal, Union Negotiator Says

In Germany, growing voter frustration has fueled the rise of the far-right Alternative for Germany — known as the AfD — which Benner sees as a threat to the country’s push to reset its manufacturing base for the green economy. The party, which gained in recent state elections in Bavaria and Hesse, has objected to technologies such as heat pumps, undermining efforts to attract investors and establish industrial clusters for manufacturing the machines. And its avowedly anti-immigrant position threatens to worsen Germany’s longstanding worker shortage.

“People need confidence. They need a plan and they need to see strategies. They need strong unions,” Benner said. “We see it as our role to push back against this political fragmentation and polarization.”

Her rise at the overwhelmingly male IG Metall is remarkable. And alongside Volkswagen works council chief Daniela Cavallo, who is leading the fight against painful cutbacks, it reflects a broader shift in Germany’s traditionally male-dominated workers’ leadership.

German rules requires 50% employee representation on the supervisory boards of large corporations — a requirement some have blamed for slow restructuring at troubled firms like Volkswagen and Thyssenkrupp AG. Benner disagrees.

“We can see that when we really push things and present good concepts to companies and governments, good things happen,” Benner said.

That’s the message she aims to deliver to Tesla, where more than 1,000 staff showed up at the EV-maker’s plant in Gruenheide near Berlin earlier this month wearing stickers calling for “safe and fair work,” IG Metall said. Tesla employees are complaining about poor conditions and safety hazards, including extreme workloads due to staff shortages and overly ambitious production targets, according to the union. Tesla said the plant has regular checks by local authorities and that safety measures were being respected, according to Reuters.

Read more: Tesla Staff Push for Safe and Fair Work in Germany, Union Says

Benner hopes to sit down soon with the world’s richest man.

“Elon, what’s the problem?” Benner said. “I’m so friendly, I’ll bring cookies.”