Under the controversial proposals, country of origin labelling would be compulsory for certain milk and meat products.
But the umbrella body for Europe's diary sector has complained, saying the move, due to come into force in January, "would hinder" the free movement of goods among member states.
In a letter to the European Commission, the European Dairy Association (EDA) also claims the French decree would "substantially violate" EU regulations.
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The association is also critical of the Commission itself for "allowing the adoption" of the French decree.
"In doing so," said the trade body, "the Commission has failed to defend the single market and opened the gateway for national measures which threaten the very fundamental principles of the treaty."
In 2015, France drafted a legislative decree requiring producers of milk, food containing milk products and food containing meat to provide information on the country of origin of the products.
The labelling rules would apply only for a preliminary period from 1 January 2017 to 31 December 2018.
On 1 July 2016, the association expressed "serious concerns" to the Commission about the initiative.
In the association's view, the "French anti-single-market approach" challenges the functioning of the EU's single market by reintroducing national barriers among member states.
"Unjustified national rules on mandatory origin labelling will hinder harmonised implementation of the food information regulation," it says.
The EDA consequently asked the Commission to "clearly speak out" against the French decree and lodged a formal complaint about it with the EU ombudsman.
Ombudsman Emily O'Reilly inquired into the matter and, in a ruling, found that the Commission's implicit approval of the French measure complied with the relevant legal requirements.
The Irish-born official also found that it was "not clear" in what way the EDA considers the Commission to have failed to make sure that France had complied with the relevant substantive requirements.
A spokesperson for the Strasbourg-based ombudsman said she had "found that at this stage the complainant had not yet demonstrated maladministration on the part of the Commission."
An EDA spokesperson reacted by telling this website, "Mandatory origin labelling in one or a few member states will further deepen the fragmentation of a harmonised legislation on the food information to consumers."