McLaren is exploring its options for a potential move away from customer Mercedes power for the next regulations period beginning in 2026.
Just last November, the Woking based team extended its deal with Mercedes all the way until 2030.
But with Alpine now considering axing its works Renault engine program, Mercedes is the frontrunner to land another customer deal to replace the Honda-bound Aston Martin.
Auto Motor und Sport claims McLaren, and also Williams, are nervous about whether Mercedes can still handle a third customer for the even more complex hybrid power units required from 2026.
Mercedes boss Toto Wolff admits he is keen to do a deal with Alpine.
"Only when they have taken the strategic decision of whether they want to continue their engine program or not, we would dive into our agreements," he said.
McLaren CEO Zak Brown admits he has visited the headquarters of Red Bull’s new Red Bull Powertrains project, which is being set up in collaboration with Ford.
"I have a great relationship with (Ford CEO) Jim Farley," said the American. "We met last year and then visited the factory. That was before we decided to extend our contract with Mercedes."
Auto Motor und Sport, however, claims Brown has been in touch with Red Bull since then.
Brown, who has been publicly highly critical of Red Bull team boss Christian Horner recently, smiled: "I don’t think I’d like to be seen there at the moment."