Mercedes says its decision not to supply its customers with its latest spec of Formula 1 engine for the remainder of the season is out of concern for compromising their performance.The German manufacturer introduced its "phase four" power unit at the Italian Grand Prix in September, using its remaining seven...

Aston Martin is negotiating a shock return to Formula 1 in a tie-up with Red Bull for next season that would bring the team Mercedes engines.In a deal that is currently still under negotiation, Aston Martin would become brand partner with four-time world champion team Red Bull Racing in exchange...