Despite declaring himself "ready" to step up, Robert Kubica is not likely to be called up should Lance Stroll leave Williams before the end of this season.

As the current reserve and development driver, it would have made sense to believe the Pole, who is aiming to race for the first time since 2010, would be the man selected to replace the Canadian.

However, as the British team get set to lose title sponsor Martini and the investment of Lance's father Lawrence, money is set to stand between Kubica and his wish once again.

Instead, F2 driver Artem Markelov and GP3 racer Nikita Mazepin are both on the sidelines with some Russian backing to offer in addition to that currently coming from Sergey Sirotkin.

Mazepin likely has the deepest pocket with his own billionaire father that tried to buy Force India while Markelov is more talented with victories in the F1 feeder series.

Williams have been accused of chasing money before, both with Stroll and Sirotkin, but deputy boss Claire Williams insists the seats won't just go to the highest bidder because of a pending financial crisis.

"Lawrence Stroll was not a major investor," she claimed. "Williams existed in F1 38 years before Lawrence joined us, and we'll be here for many more years after he goes."