Williams deputy team principal Claire Williams says her team supported Marussia's return to the Formula One grid with its 2014 cars.
A move to allow the struggling Marussia team to compete with last year's cars was blocked by Force India last week during a Strategy Group meeting.
While Force India claimed Marussia's bid lacked substance, the latter is still planning to come out of administration on February 19 and says its return to racing is still viable.
We want a full competitive line-up on the grid next year and we will do anything to support Marussia coming back in.
Williams, whose outfit is one of six teams in the Strategy Group, says the Grove team was always in favour of Marussia's comeback.
"We want a full competitive line-up on the grid next year and we will do anything to support Marussia coming back in," Williams told Sky Sports.
"We made it very clear in the Strategy Group that we would vote for them to be able to use the 2014 chassis this season.
"Unfortunately it hasn't happened, but Williams want a competitive line-up on the grid and we want to help the smaller teams.
"And I think we've demonstrated that and are always pushing cost control in Formula One.
"That's to save the smaller teams that are really struggling, the likes of Marussia and Caterham, but also the middle teams as well at the moment that are facing some serious issues."