Pirelli is to strengthen its tyres for the German Grand Prix after a series of dangerous blow-outs at Silverstone that led to calls for urgent action, the BBC reported on Tuesday. The broadcaster said on its website that the Italian manufacturer would make the rear tyres\' internal belt with the high-strength synthetic fibre Kevlar instead of the usual steel to reduce temperatures and the risk of punctures. Safety concerns were expressed after Sunday\'s British Grand Prix after Lewis Hamilton of Mercedes, Jean-Eric Vergne of Toro Rosso and Sergio Perez of McLaren all suffered blow-outs. Formula One teams, Pirelli and motorsports world governing body the International Automobile Federation (FIA) have called a meeting at the Nurburgring for Wednesday to discuss the matter. The BBC did not quote sources for its story but said that Pirelli was expected to announce the changes later on Tuesday. Only the rear tyres will be changed for Sunday\'s race, although a complete change would be introduced for the Hungarian Grand Prix on July 28 using the 2012 design, it added. From: AFP