Toto Wolff has admitted for the first time that Valtteri Bottas is a "possibility" to replace Nico Rosberg at Mercedes.

Sources in Spain report that Williams are pushing for the German marque to reduce their engine bill to zero, in exchange for Finn Bottas's eleventh-hour release.

"It's too early to say," Wolff told La Gazzetta dello Sport. "We have not yet made a decision, because it involves more than one driver and one team. And we have respect for the other teams.

"Valtteri is a possibility but we also know how important he is for Williams. It's a delicate situation which requires us to move cautiously, so we decided to take a bit of time."

The Austrian played down claims that if Bottas is signed, a conflict of interest and an unfair situation for Lewis Hamilton would be created, because the Finn is managed by Wolff himself.

"I'm not an idiot," Wolff insisted. "When I started with Daimler four years ago, I made a deal that I cannot manage or have business interests with a Mercedes driver.

"Those who talk about a conflict of interest are illiterate about F1."

Yet there is already tension with Hamilton, with the Briton suggesting recently that he will no longer accept the pre-season loss of key mechanics and engineers from his side of the garage.

"This is an old story," Wolff responded. "He understood why we moved in that direction, and I understood his side from the psychological point of view."

The 2017 calendar is scheduled to get underway with the Australian Grand Prix on March 26.