The European Commission has given provisional backing to France’s decision to block the sale of most of new Mercedes-Benz cars because they contain a banned refrigerant.

The Commission’s assessment is a blow for Mercedes parent Daimler and could also open the way for similar restrictions on Mercedes sales by other EU countries.

“Currently in the European market there are vehicles produced by this manufacturer that, according to the preliminary Commission analysis, are not in conformity with their type-approval,” EU industry chief Antonio Tajani said in a statement.

Further assessment is needed to determine if some Daimler cars produced since May under a previous approval granted by the German authorities are also illegal, Tajani said. Any vehicles that do not conform cannot be sold or registered in Europe.

As a result, France’s refusal to register Mercedes cars built since June 12 may be considered legal under existing EU rules, provided the right procedures are followed, Tajani said.

French authorities have refused to register Mercedes A class, B class and CLA cars, even though German authorities have approved them, because the vehicles contained the R134a refrigerant that is not permitted in the EU.

Daimler has said its refusal to phase out R134a – a potent global warming agent – is justified by safety concerns over the only available replacement, Honeywell International’s R1234yf.

A Daimler spokesman said the cars had been approved by the German authority, the KBA. “Our cars have a valid, European-wide permit. Nothing should stand in the way of their being registered.”

Based on 2012 deliveries, Daimler has said the French block could affect about 2 percent of its global sales, or 29,000 cars.

EU government officials are due to discuss the issue at a meeting in Brussels on Wednesday.