Williams has confirmed that both Valtteri Bottas and Felipe Massa will be on duty at next week's opening pre-season test at Jerez.

While speculation continues as to whether McLaren will follow Lotus' example and miss the test, the Woking team rumoured to have failed at least one of the mandatory crash tests, Williams has confirmed that it will be joining those teams that have already confirmed their presence including Red Bull and Mercedes

"We can announce we will be on track in Jerez," the team tweeted this afternoon. "Valtteri Bottas will do days 1 & 2 Felipe Massa days 3 & 4 running our heritage blue livery".

On Saturday evening the team revealed that it had fired up its new Mercedes power unit for the first time.

"Frank in race bay this evening as the FW36 fires up for the first time!" the team tweeted. "2014 starts here."

The team had tweeted its intention to be at Jerez over a week ago, however, in light of the speculation over McLaren and the failure to announce an official unveiling, some remained sceptical.

With the Grove outfit still to officially announce a launch date it must be assumed that the FW36 will either be unveiled over the weekend or on Monday, ahead of the first day of testing like Toro Rosso, or on the morning of the first day of the test like Red Bull and Mercedes.

Chris Balfe