The US Trade Representative's (USTR) Office concluded on Monday that France's digital services tax discriminates against US firms and is proposing additional duties of up to 100 percent on certain French products in retaliation.

Moreover, the USTR is "exploring" whether to open investigations into the digital services taxes of Austria, Italy, and Turkey.

Dozens of French products with a trade value of some 2.4 billion dollars may be subjected to the duties, the USTR's Office said.

"The French DST is unreasonable, discriminatory, and burdens U.S. commerce," the USTR said. "USTR's investigation found that the French DST discriminates against US digital companies, such as Google, Apple, Facebook, and Amazon."

The proposed retaliation is being opened up to public comment until early January, when hearings will begin.