The European Commission is expected to launch legal action against Germany over Daimler's refusal to remove a banned refrigerant from new cars, EU sources said on Monday (20 January).
A final decision on legal action against Germany could be taken as early as Wednesday, said two sources, speaking on condition of anonymity.
Officials have for months been investigating the German luxury carmaker's refusal, backed by Berlin, to follow an EU law banning the air-conditioning coolant known as R134a from the start of last year.
The carmaker insists its refusal to phase out R134a, a global warming agent more than 1,000 times more potent than carbon dioxide, is justified by safety concerns.
The only available replacement, Honeywell's R1234yf has a global warming potential only four times more than carbon dioxide but Daimler says it can emit toxic hydrogen fluoride gas when it burns.
"Germany could so far not prove that R1234yf is so dangerous that a violation of the rule is justified," one of the EU sources told Reuters.
A second said: "The opening of the infringement procedure is imminent. If it will not be at this round of infringements, it will be next month."
After safety tests, other European carmakers have switched their newest models to the coolant developed by Honeywell in partnership with Dupont.
The Commission said it could not comment before Wednesday and Daimler also said it could not comment.
Under the EU infringement system, countries found not to be enforcing the bloc's law can be taken to the European Union's top courts in Luxembourg, which have the power to impose fines.