Force India is waiting on Ferrari to finalise its driver line-up before it can confirm Nico Hulkenberg for 2015.

The team is keen to retain both Hulkenberg and Sergio Perez for next season after impressive performances from both drivers during this year, but would like to announce their signings together. Fernando Alonso leaving Ferrari has held up that confirmation despite Sebastian Vettel being poised to join, but deputy team principal Bob Fernley told Crash.net exclusively that an announcement should be possible soon.

"There are always elements in contracts that just have to be finalised out," Fernley said. "Those will be done over the next week or two, but fundamentally it's a done deal for going forward.

"Maybe not by Austin, we're not always the quickest to announce our driver line-ups!"

And when asked if part of the delay was due to the uncertainty surrounding Ferrari's driver line-up for 2015, Fernley admitted that had held up Hulkenberg's confirmation.

"There's an element of that, yes, because obviously that's part of the contracts we have with Nico. So we have to take that in to consideration. Those are the elements that delay things slightly and then obviously you finish them off."

Asked if confirmation of Vettel joining Ferrari would help Force India finalise its contracts, Fernley replied: "Yes, it clarifies things."