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Mercedes, who could face -expulsion from this year's world championship should the FIA international tribunal find against them next month, continued to protest their innocence as the
controversy escalated after Nico Rosberg's Monaco Grand Prix win The row over Mercedes' private tyre-test deepened on Monday, as it emerged that the Silver Arrows had already
received an explicit warning that in-season testing by a single team was banned under Formula One rules. Mercedes, who could face -expulsion from this year's world championship should
the FIA international tribunal find against them next month, continued to protest their innocence as the controversy escalated after Nico Rosberg's Monaco Grand Prix win. But as Toto
Wolff, the Mercedes motorsport director, maintained that the 600-mile test in Barcelona a fortnight earlier had been "exactly to the rules", his account did not square with an
email sent to them last year by the Formula One Teams' Association, clarifying that such a test could only take place with the "unanimous" support of all teams. Although
Mercedes maintain they had received more recent permis-sion from the FIA to test their tyres, their actions aroused fury in their chief rivals - not least reigning world-champions Red Bull,
whose team principal Christian Horner labelled the episode "underhand". A broad range of sanctions is open to the FIA tribunal when it convenes, from docking Mercedes the 37 points
they earned in Monte Carlo to throwing them out of the championship. Horner said: "What is wrong is that a team have, in an underhand way, consciously tested tyres designed for this
year's championship. The rules are very clear. You sign up to those regulations and by doing that Mercedes have not complied." Ferrari principal Stefano Domenicali was furious at
the revelation, insisting he wanted his team to be given the same privileges. "For us, there is not a doubt the 2013 car was used and, as is written in the regulations, the two previous
years' cars cannot be used in the season in this way." Meanwhile, Kimi Raikkonen has said that "someone should hit Sergio Perez in the face", after Perez blamed the Finn
for an accident in Monaco that cost both drivers dearly. The 69th-lap shunt saw Raikkonen suffer a puncture and Perez retire from the race with a brake problem. The Mexican's
risk-taking style is often criticised and, when asked if the drivers should get together and speak, Raikkonen said: "I don't know. It is maybe better to hit him in the face and
then he'll understand."