Red Bull sets new deadline to secure 2016 Formula 1 engine deal

Mateschitz has given team principal Christian Horner and Red Bull motorsport advisor Helmut Marko a three-week extension to resolve the situation, having originally stated the situation had to be resolved by the end of October.

"I extend the deadline for three more weeks," said Mateschitz, which means his team chiefs have until the weekend of November 21-22 to come up with a solution.

"The situation is clear, we won't get any of the existing powertrains because all teams fear that we would be faster than their own works outfits.

"As we know you can't buy courage or sporting spirit."

Red Bull has failed to land Mercedes or Ferrari engines since deciding to split with current supplier Renault, while talks with Honda appear to have stalled due to McLaren Group CEO Ron Dennis being against a deal.

Horner claimed over the Mexican GP weekend Honda is , while prior to that McLaren racing director Eric Boullier said his team "is not a charity foundation" that has to solve problems "created by Red Bull".

Mateschitz added: "There remain a few complicated solutions, however I do not know if I should be going through these."

Horner stated "there may be something else" available as an option to Red Bull for 2016, although Mateschitz denied rumours of the team being sold to Renault.

Autosport understands a Renault engine deal remains an option to Red Bull, as the French manufacturer is yet to confirm the split.

While Red Bull has been outspoken in its criticism of Renault's performance, Horner described the unhappy relationship of the last two years as "not a one-way street".

"You have to understand all of the history, the background and the circumstances," he said.

"It's always easy to look with hindsight but there's been a lot of things said on both sides."

Horner added in Mexico that Red Bull is now "right on the limit" to be able to get its 2016 car ready in time for the first pre-season test on February 22.

Toro Rosso, the second team owned by Red Bull, is understood to be close to finalising an agreement to run year-old specification Ferrari engines next season.