Formula 1 drivers have threatened to boycott Sunday's German Grand Prix if there is a repeat of the tyre failures experienced at Silverstone.
The Grand Prix Drivers' Association, which represents the vast majority of drivers, said its members wanted to express their "deepest concerns".
The GPDA added: "If similar problems manifest themselves at the German GP, we shall immediately withdraw."
Six drivers suffered failures during the British Grand Prix last weekend.
Mercedes' Lewis Hamilton, Ferrari drivers Felipe Massa and Fernando Alonso, Toro Rosso's Jean-Eric Vergne, Sauber's Esteban Gutierrez and McLaren's Sergio Perez were all affected.
Tyre supplier Pirelli has produced a tyre of a different design for this weekend's race in an attempt to solve the problem.
The GPDA statement said: "We trust that the changes made to the tyres will have the desired results and that similar problems will not occur during the German GP weekend."
Red Bull driver Mark Webber said: "Actions speak louder than words and Pirelli has to do something from a safety perspective.
"Performance is one thing but when you have safety involved, you have to find the right way for all of us.
"Silverstone was a very dramatic and extremely unsafe scenario for all of us.
"But I'm not driving a car this weekend worried about the tyres."
Earlier on Thursday, Alonso described the experience of being right behind Perez when the Mexican's tyre failed.
The Spaniard, who was travelling at 179mph, said: "It was a dangerous situation.
"I committed to overtake Sergio on the left. I was lucky because maybe if I chose the right, everything would hit my helmet.
"There are pieces of steel coming at 300kph so it would be like a bullet or a knife."
He added: "Pirelli made some changes. We trust them. We think they solve the problem."
The GPDA is chaired by Pedro de la Rosa, with Sebastian Vettel and Jenson Button as directors, but Hamilton and Lotus driver Kimi Raikkonen are not members.
It has been concerned for some time about the number of tyre failures this season.
After a series of delaminations, when the tread separates from the tyre but it stays inflated, in the early races it asked the sport's governing body, the FIA, for a reassurance changes would be made.
Pirelli wanted to introduce for the Canadian Grand Prix last month the tyre that is finally being used in Germany this weekend but was blocked by three teams who felt the move might harm their competitiveness.
Pirelli refused to say at the time that there was a safety issue, and the rules dictate that tyres can only be changed for other reasons during a season with unanimous approval of the teams.
But following the problems at Silverstone, which all agreed were unacceptable, the FIA has stepped in and forced through a change, which all teams now accept was necessary.
Pirelli issued a statement on Tuesday blaming the failures on teamsnot running the tyres according to its guidelines.
But Button said: "We followed all of Pirelli's guidelines - on both cars."
