Williams have cancelled a planned 'shakedown' run of their new F1 car before the first official pre-season test because of delays building it.
The team, who were bottom of the constructors' championship last year, had aimed for a "filming day" in Barcelona on Sunday.
Williams say they are trying to maximise development time on the car.
"We have had an aggressive engineering programme over the winter," said deputy team principal Claire Williams.
"As such, we have taken the decision not to run our car during our filming day this weekend in order to allow the team to maximise the time at the factory before we head to Barcelona for the first day of the test on 18 February."
Renault F1 boss Cyril Abiteboul has said his team may not make it to a planned shakedown on Saturday in Spain.
F1 teams are allowed a limited number of filming days each year, when mileage is limited to 100km and the car must run on non-race tyres.