Mercedes could limit its customer engine supply in F1 to two teams instead of three in the future, as its business of leasing engines is no longer "compelling".
Mercedes' High Performance Powertrains unit at Brixton currently supplies the German manufacturer's works outfit and three customer teams, McLaren, Aston Martin and Williams.
While power units are excluded from Formula 1's $140 million cost cap, the cost of purchasing an engine supply from a manufacturer has been capped by the FIA at $15 million.
However, Mercedes team boss Toto Wolff says production costs and fine margins mean that the German manufacturer is no longer earning "substantial amounts" from its supply deals, and their profusion is not an advantage.
"Unfortunately, the business of leasing engines is not compelling and interesting because the FIA has put in a certain limit that you can charge to your customers, in order to protect the smaller teams," Wolff told The Financial Times.
Wolff's comments come at a time when his works outfit has lost its dominant position in F1 and is struggling to bridge the performance gap with its Ferrari and Red bull rivals.
Wolff hinted at a potential reduction of its customer supply deals in the future, although the Austrian offered no clue as to which of its three customer teams could be dropped from its offerings.
"I’d rather have six [client cars], push the development further down the line and then make two engines less, because you need to produce two less plus two spares for every team," he said.
"In an ideal world, I would maybe see us, plus two [customers], so actually downsize a bit."
Mercedes enjoys a historic relationship with McLaren that goes all the way back to 1995, while its long-standing partnerships with Williams and Aston Martin - ex-Racing Point and Force India - have been in force for well over a decade.
However, the expected arrival in F1 of Porsche and Audi could imply new collaborations for any one of Mercedes' current three customer teams.
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