Force India is holding off on confirming Lance Stroll for 2019 out of "courtesy" to Esteban Ocon.
It is an open secret that Ocon will be ousted and replaced with Stroll, whose billionaire father Lawrence has bought the team.
"We will not announce the other driver until Esteban’s future is clarified," team boss Otmar Szafnauer said.
"There’s no reason to rush, simply out of courtesy. It would be good if Esteban could announce his future himself."
Force India then hopes to have the deal in place for Stroll by Abu Dhabi, when the Canadian could get an early start by participating in the post-race test.
"The second driver will definitely do the winter tests, but if he can test already in Abu Dhabi that would be ideal.
"Those tests are aimed at 2019, and we’ll get to use the new tyres," Szafnauer added.