MONTE CARLO, Monaco, May 27, 2013 (AFP) - Red Bull team chief Christian Horner accused triumphant Monaco Grand Prix rivals Mercedes of "underhand" activity on Monday as the dust finally settled following Sunday's turbulent race won by local hero German Nico Rosberg.
Horner, who joined Ferrari in lodging a protest on Sunday against Mercedes for allegedly taking part in an illegal in-season Pirelli tyres test, said he was most aggrieved at the manner in which the German team had behaved.
The sport's ruling body, the International Motoring Federation (FIA) was still on Monday awaiting a report from stewards at the Monaco Grand Prix, with whom the protest was lodged.
Horner said: "What is wrong is that a team, in an underhand way, consciously tested tyres that were designed for this year's championship.
"We view that the testing rules are very clear in the sporting regulations and when you enter the championship at the beginning of the year you sign up to those regulations.
"We put in a protest because we wanted clarity more than anything. We talk an awful lot about saving costs.
"We spent three hours on Friday (in a team principals' meeting) talking about in-season testing and trying to find a solution, and it turns out one team has already done a huge amount of it."
Horner's blast at Mercedes came after seeing Rosberg produce a superb drive from pole position to resist Red Bull pair, defending drivers' world champion German Sebastian Vettel and Australian Mark Webber, who, thanks to some luck with the delayed introduction of the first Safety Car, managed to push Briton Lewis Hamilton, in the second Mercedes, back to fourth.