Beijing slammed on Monday an EU plan aimed to bolster the bloc’s industries against fierce competition from China, vowing countermeasures if it is enacted.

The EU unveiled in March new “Made in Europe” rules for companies trying to access public funds in strategic sectors including cars, green tech and steel, obliging firms to meet minimum thresholds for EU-made parts.

The proposal, held up for months by wrangling over the measures, is a key part of a European Union drive to regain its competitive edge, reduce its industrial decline and stave off hundreds of thousands of job losses.

Beijing’s commerce ministry said on Monday that it had submitted comments to the European Commission on Friday, expressing China’s “serious concerns” regarding the act it called “systemic discrimination”.

“If the EU… presses ahead with the legislation, and thereby harms the interests of Chinese companies, China will have no choice but to take countermeasures to firmly safeguard the legitimate rights and interests of its enterprises,” the commerce ministry warned in a statement.

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European businesses in many of the sectors concerned by the proposal have long lamented they face unfair competition from heavily subsidised Chinese rivals.

The EU proposal, formally known as the “Industrial Accelerator Act”, implicitly targets Chinese makers of batteries and electric vehicles by requiring foreign firms to partner with European firms and pass on technological know-how when setting up shop in the bloc.

The Chinese Chamber of Commerce to the EU said this month the plan marked a shift towards protectionism that would affect trade cooperation between the EU and China.