Former Formula 1 driver and Toro Rosso shareholder Gerhard Berger doubts the top man at Red Bull, Deitrich Mateschitz is getting tired of his investment in the sport, despite speculation of future sales.

The Austrian remains a close friend of the billionaire CEO, despite selling his stake in the junior team back to Mateschitz in 2008 and is, therefore, one of the best placed to analyse the mood towards the current state of F1. 

Recently there has been talk the new Honda tie-up with the Faenza-based team could lead to an eventual sale to the Japanese manufacturer, while Porsche taking over the current Milton Keynes outfit in 2021 is also thought to be a possibility. 

However, the former McLaren, Benetton and Ferrari driver believes Red Bull is not going to give up on the sport yet, despite regular prior threats from advisor Helmut Marko.  

"To think that he is tired of Formula 1, I think is wrong," Berger told the Austrian broadcaster ORF. "Of course, he isn't happy with the current situation of his team but Red Bull is still a super strong team, and even in this difficult time hardly anyone has left, especially Newey at the top."

The main issue Red Bull has constantly aired is the current dominance of engines on performance, which ended their period of success after 2013 and sees them potentially struggling to catch up until new rules in 2021. 

"Not having an engine that can bring title chances is, of course, frustrating in the long term," Berger added.

Nevertheless, he does see positives from Toro Rosso's deal with Honda, believing the two parties can work better together than McLaren did and the opportunity for Red Bull to benefit too.

"Red Bull has always had patience, and now is when it's needed. It cannot always go well," he said "It's a difficult time now, but you can see the light at the end of the tunnel. Honda coming to Toro Rosso is the start.

"I believe in Honda, who have a sporting culture in the company, the resources and now a team with the Red Bull mentality. I could imagine Honda returning to its original form and building top engines."

In Singapore, the prospect was raised of Aston Martin increasing their participation, along with the admission they were considering becoming an engine supplier from 2021.

"We have to wait for the new engine regulations," Berger commented. "Until then nobody will burn their fingers on today's extremely difficult engines.

"Does Aston Martin Martin have the resources and the possibilities to do it? I don't know but I doubt it."