Red Bull have reportedly entered talks with Ferrari over a possible engine deal with the Italian marque.
The Milton Keynes-based constructor has had a public falling-out with existing engine partner Renault over the performance of their power unit following a poor start to 2015.
According to Sport Bild, Red Bull are now fed up of reliability problems involving the French manufacturer and have been in negotiations with the Scuderia.
Recently, the former constructors' champions were also rumoured to be in talks with Volkswagen, who are widely thought to be plotting a way into Formula 1.
Red Bull were previously powered by Ferrari engines in 2006.