Mercedes boss Toto Wolff says Mercedes must think carefully when it comes to finalising its 2020 driver line-up.
Esteban Ocon, a Mercedes junior driver, lost his racing seat at the end of the 2018 season, and has been linked to the Mercedes drive, as well as drives with other teams.
"We’re very happy with the development of Esteban and equally George," Wolff said. "They are our most senior junior drivers and the aim is to make them ready for a seat in a Mercedes.
"And as we all know, it was an unfortunate situation last year that Esteban fell between the chairs. He could have chosen between two seats and in the end nothing came out so from our perspective everybody knows about his driving capabilities.
"For Mercedes, for ourselves, Valtteri is showing some very strong performances and merits the seat but equally Esteban has shown that in the past and is a great addition to the team.
"He contributes a lot behind closed doors. He drives the sim overnight on race weekends, comes in here on Saturday and gives us input and he’s a great kid overall."
Mercedes has not yet promoted one of its young drivers to the senior team, while Ferrari signed up its junior driver Charles Leclerc for 2019 - and Red Bull only operates under the 'promotion' system.
"Putting a Mercedes young driver in the car would be interesting as well. Having said that, there is interest for Esteban among other teams and we need to carefully make a decision for ourselves and with the other interested parties, not only for our own benefit but also for Esteban’s benefit.
"And if it would mean that we are taking a decision in favour of Valtteri, it clearly also means that somebody else would continue to develop him and would mean that we would lose our hand for a year or two or more on Esteban and these are the consequences of that decision."
Ocon has also been linked with a race seat at both Haas and Renault for 2020.