Marianne Thyssen has blasted a law that bans anything other than French languages on building sites
Earlier this month, Paris officials passed a ‘Small Business Act’ in a bid to funnel more local public contracts to small French businesses.
The move is also reportedly to help improve workplace safety and "squeeze out" foreign workers.
The act includes the hotly-contested Molière clause, which states that labourers hired to work on state-funded building projects must use French as their working language.
But Marianne Thyssen, the EU commissioner for employment and social affairs, has blasted the act.
She told Le Parisien: “The Molière clause is discriminatory and blatantly violates EU rules on public procurement.
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"It is not by turning inwards and by shunning foreign workers that France will solve its unemployment crisis. In addition, this form of hardline protectionism is not in France’s best interests."
The Molière clause is discriminatory and blatantly violates EU rules on public procurement
European rules on public procurement bar member states from discriminating against companies from another EU countries uniquely on grounds of their nationality.
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But French officials have openly criticised this rule and have long argued that it allows French companies to hire cheap foreign workers – often from eastern Europe – who undercut locals.
Mrs Thyssen claimed that dismissing EU rules on public procurement was a 'bad idea'
Mrs Thyssen added that dismissing EU rules on public procurement was a “bad idea” because they helped prevent “social dumping”.
She added: “The freedom of movement for workers is one of the founding principles of the EU. And French firms cannot under any circumstance attempt to circumvent EU rules.”
Paris was the fourth region to introduce rules requiring companies to use the French language on public building sites, after Normandy, Hauts-de-France and Auvergne-Rhone-Alpes.