Contrary to reports, Williams has not yet debuted its 2012 car.
It was said the British team ran the unlaunched FW34 at the Idiada facility near Barcelona, with tester Valtteri Bottas at the wheel.
In fact, "the shakedown could not take place due to bad weather conditions," a spokesperson is quoted as saying in the German press.
Pastor Maldonado will instead give the newly Renault-powered car its maiden outing, at Jerez on Tuesday.
With the rollout of the new Ferrari cancelled in Italy due to similarly bad weather, it means the Force India is the first 2012 car to have run on a circuit.
Paul di Resta drove the VJM05 at Silverstone after its launch on Friday.
"It looks good and it feels great and I look forward to running it again in Jerez on Tuesday," the Scot is quoted by the Guardian.