The Mercedes Formula One team will be formally investigated by the International Tribunal of motor racing's ruling body, following allegations of illegal in-season testing with Pirelli tyres.
The FIA's international tribunal has wide-ranging powers and if it finds Mercedes guilty can impose penalties ranging from fines to exclusion from the world championship.
The announcement that the German team is to be investigated further follows a report by the stewards at the Monaco Grand Prix, in the wake of protests lodged by Ferrari and Red Bull.
The announcement is not expected to have any effect on the team's preparations for this weekend's Canadian Grand Prix in Montreal.
