Ferrari have taken a swipe at Williams after they blocked their bid to test Michael Schumacher in this season's car.
Ferrari last week wrote to the other nine Formula One teams and the FIA requesting Schumacher be granted a day at the wheel of the F60 given he has been retired for almost three years.
The seven-time world champion is due to return to racing at the European Grand Prix in Valencia on August 23 in the absence of the injured Felipe Massa.
But Williams adhered to the letter of the law that prohibits in-season testing, with team boss Frank Williams seeing no reason why Schumacher and Ferrari should be granted special dispensation.
That clearly angered Ferrari, who have made their frustration clear in an article on their official website, initially taking a pop at Williams.
"Guess who opposed the test with the F60?" questioned Ferrari.
"A team that hasn't won anything for years and yet didn't pass over the opportunity to demonstrate once more a lack of spirit of fair play."
Williams have also been backed by Red Bull Racing and Toro Rosso, who were not allowed to test 19-year-old Jaime Alguersuari prior to his debut with Toro Rosso in Hungary.
Ferrari added: "Just for the record, the Scuderia Ferrari had given its approval to let Alguersuari test.
"But it seems even in this instance someone decided to stick to the precise wording of the regulations."