Robert Kubica insists he is ready to go should he get the call to replace Lance Stroll, as the Canadian's inevitable move to Force India edges closer.

After reports the 19-year-old could make the move as soon as the Italian Grand Prix next weekend, the latest update from RaceFans is he will have a seat fitting at Silverstone on Tuesday which would back up the Monza theory.

If that does turn out to be the case, Kubica would be the only realistic choice for Williams to step up but that possibility doesn't phase the 33-year-old who has been in the role of reserve and development driver all season.

“I feel ready because otherwise, I would not sign a contract with Williams for this year,” he told Autosport. “It’s on my desk that, ‘You have to keep being ready and in case something happens, you have to step up’.

“Of course, it is not easy when you have to drive against the top drivers in the middle of the season. Although I have some opportunities to drive the car, you still lack experience, but you have to do it.

“I also think when Williams approached me for this role, they also have no doubts that I can do it but what’s happening currently and a lot of speculation is not affecting myself.

“I’m doing my job and then what the future will bring, we will see.”

When Stroll makes the move, it is all-but-confirmed that his teammate will be Sergio Perez, who admitted his future has been decided although the announcement was on hold.

The Mexican was asked for his thoughts on Lance, whose reputation is being hit again by the notion of his father buying his career.

“I think it’s so hard to know someone as a driver when you are not being alongside him,” said Perez. “There is so much difference in Formula 1 across teams performance, between cars you see a difference of two-and-a-half seconds or so.

“I think he did not too bad alongside Felipe [Massa] which I think is a very experienced driver. Right now Williams is in a very difficult position so it’s very hard to judge.

“I think he’s grown up, he has good experience now with two years at Williams, we’ll see what he’s able to do in that regard. It’s very hard to judge someone when they’re not your teammate.”