Toro Rosso’s cars could turn yellow, Red Bull official Dr Helmut Marko has admitted.
As he criticises engine partner Renault for its retrograde step in 2015, Marko has also confirmed that talks with the French marque about stepping up its involvement in the sister team Toro Rosso are taking place.
"If Renault believes it must represent itself differently for marketing reasons, then they are talking about either buying a team or having two cars in yellow," the Austrian told Speed Week.
Marko said similar talks have also taken place between Renault and Sauber, Force India and Lotus.
As for the Toro Rosso talks, he said owner Red Bull is open to Renault’s ideas.
"If it improves performance and facilitates cooperation, then yes," said Marko.
"If Renault is happy with such a solution, then we are happy to talk to them. It is not just about the possibility of a sale, there is also the option to just give them (Renault) two cars in yellow."
There are also rumours Red Bull could be thinking of selling its premier team to Audi, having threatened in Australia to quit F1 in protest of the engine rules.
However, insiders have pointed out that Red Bull is contractually bound to F1 through 2020.
Marko, denying there are "any talks" with Audi, insisted: "BMW and Toyota also had long-term contracts."