Niki Lauda says Mercedes could wait until the end of January before it decides on Nico Rosberg's replacement for 2017.
The Mercedes chairman said his team faces a "huge decision" as it weighs up Mercedes junior driver Pascal Wehrlein and Williams' Valtteri Bottas for the position. Mercedes would have to buy Bottas out of his current contract if it wanted to employ him next year and Lauda admitted the complex discussions are taking longer than expected.
"It could take until the end of January before we know which way we will go," he said in an interview alongside Red Bull's Helmut Marko on Servus TV. "We are not yet that far and we don't know yet. We hoped to make it sooner, but they are quite complicated negotiations.
"Basically, there are just two ways to go: a young driver like Wehrlein, who could become a star or could not, or we an experienced man like Bottas. We are far from being ready with these considerations -- this is a huge discussion. "
Sat next to Lauda, Marko could not help but challenge his old friend and rival. Marko is the head of Red Bull's junior driver programme, which has seen the likes of Sebastian Vettel, Daniel Ricciardo and Max Verstappen enter the sport, and he put it to Lauda that Mercedes, which has a long-term contract with Wehrlein and placed him at Manor this year, does not have enough trust in its driver development system.
"You have a junior programme and you have the highly regarded Mr. Wehrlein," Marko said. "This guy Wehrlein does not look like he will get the drive. That means you do not trust your own junior programme. "
Lauda responded by saying: "I must correct that. The junior programme is, as you say, a junior programme. Young pilots should gain experience.
"Clearly, we can discuss whether Wehrlein is ready or not, but I'd like you to remember that Max Verstappen first started out at Toro Rosso this year until the Russian [Danill Kvyat] made a mistake and only then did you take him over to the senior team."
Marko added: "Well, Wehrlein is still very young -- but no risk, no fun. If you take Valtteri Bottas, you have to give a two-digit million amount in the form of a reduction in engine costs to Williams. Well, you have a budget of 22 million now that you are not paying Rosberg, but you have to buy Wehrlein a drive at a team that drives a competitor's engine [Sauber]."
Mercedes has not set a formal date for a decision other than confirming that it will not be announced before the start of the new year.