Horner: No regrets over Renault criticism

Amid frustrations about the lack of engine performance this year, Horner criticised the French car manufacturer several times as relations between them broke down.

And it was Red Bull's attitude in being so negative with its engine partner that was cited as a reason why Mercedes was not eager to conclude a customer deal, for fear it too could have a publish bashing.

When asked by Motorsport.com if, knowing how events panned out, he regretted his approach, Horner said: "It is very easy for others to pick up and use whatever excuse is convenient.

"What you have to remember is, this is a competitive business. As far as I am concerned, I have only ever told you the truth.

"When I have been asked a question I have given you an answer. And if you look at actually what I have said, I don't think there is anything particularly unfair in the comments that have been made.

"I think it is inevitably born out of frustration – comments that either Dietrich [Mateschitz], or Adrian [Newey], or Helmut [Marko] have made."

Wider motive

Horner suggested that part of the reason to go so public with his feelings, rather than keep it behind closed doors, was that he felt it was the only way the Renault board would be aware of how big the problems were.

"Of course it is never good to conduct your business in public, but it was really born out of frustration more than anything," he said.

"The Renault board are quite distant from what is going on. It is not like with Dieter Zetsche, who attends quite a few races, or Sergio Marchionne.

"So part of being vocal was also to get those messages back to the Renault board: that there are some issues here and they need to be resolved."

Conservatism

Although there were suggestions Renault's early season woes were exacerbated by the manufacturer having been pushed too hard to bring developments, Horner is adamant that Red Bull did not go too far with its demands.

"I don't think so," he said. "I think that they [Renault ] are quite an established and conservative organisation, and of course our DNA is we want to push. We want to get on, and we want to make progress.

"Obviously a lot of promises were made over the last quarter of the year and the closed season of 2014/2015, so inevitably expectations rose.

"So it was frustrating to see us further away, and in fact behind where we finished the season in 2014, going into 2015."