Mercedes will face an investigation from the FIA's International Tribunal regarding its recent secret tire test with Pirelli, while Ferrari has been cleared for its test with a 2011 car.
The Mercedes test at Barcelona was referred to the stewards of the Monaco Grand Prix when Red Bull and Ferrari lodged a protest on that weekend.
The FIA had been waiting for a report from the Monaco stewards before deciding if Mercedes had a case to answer, and it has decided to pass the matter on to the International Tribunal.
How the International Tribunal works
The sport's governing body explained that it requested information from those involved and rival teams before coming to its conclusion. Ferrari's own test with Pirelli, conducted at Barcelona in April with a 2011 car, was deemed not to breach the rules.
An FIA statement said: "In the light of all the replies received and in view of the information gathered during this inquiry, the president of the FIA, acting as the FIA prosecuting body, has decided:
"To close the case as regard to Scuderia Ferrari Team considering that its participation in a tire test organised by Pirelli in Barcelona on April 23-24, 2013 using for this purpose a 2011 car is not deemed to contravene the applicable FIA rules.
"To bring the case concerning the tire testing session carried out by Pirelli and Team Mercedes AMG Petronas F1 in Barcelona on May 15-17, 2013 before the FIA International Tribunal because it results from the inquiry that the conditions of this testing may constitute a breach of the applicable FIA rules.
"The FIA International Tribunal is called upon to make a decision in compliance with the FIA Judicial and Disciplinary Rules."