LONDON, England - Mercedes and Formula 1 tyre supplier Pirelli will appear before an international motorsport tribunal in Paris on June 20, 2013 to answer charges of breaking the rules by tyre-testing in Spain.The International Automobile Federation said in a statement that a notification of charges against both parties had been sent to the president of the tribunal. "Pirelli and the Mercedes F1 Team have been convened by the president of the tribunal to appear before a judging panel."The verdict would be published as soon as possible.'PRIVATE, NOT SECRET'Mercedes' Lewis Hamilton was third in the 2013 Canadian GP but now his team could face stiff penalties ranging from a fine to points deduction or even exclusion if found guilty. The rules bar teams from testing during the season with a current car.Red Bull and Ferrari made formal protests at the 2013 Monaco Grand Prix in May when news of the test spread.Mercedes used a 2013 car at the test in Barcelona which came just before Nico Rosberg won in Monaco but the team said the test was approved by the federation. It also argued the test was private but not secret and was run and organised by Pirelli who is the sole provider rather than a "competitor" in the championship and therefore not subject to the ban that applies to teams. The team said it would welcome the chance to present its case to the tribunal and would explain the full facts in "an open and transparent manner". Stay with Wheels24 for the 2013 F1 season – fresh reports every day.