Toto Wolff admits Mick Schumacher may not be able to return to the Formula 1 grid in 2024.
There have been rumours that the 24-year-old German, who lost his Haas race seat at the end of last season, could replace the struggling rookie Logan Sargeant at Mercedes-powered Williams.
Schumacher is currently Mercedes' full-time reserve driver.
"It's a difficult situation," said team boss Wolff, "because the cockpits are taken with us.
"I would wish for Mick to get a seat as he deserves it, but the situation in 2024 is so unfavourable.
"A few doors will open in 2025," he told Sky Deutschland, "and we'll have to see how the situation develops at Williams.
"But it's not easy," Wolff admitted.
The Mercedes team boss also said he will try to make Schumacher's quest for his return to Formula 1 as low-profile as possible for now.
"We have to be careful because if we support Mick too much, there will then be those who want to make it particularly difficult as they come crawling out of their holes," said Wolff.
