F1 Canadian Grand Prix: Christian Horner maintains belief that Red Bull can hunt down runaway leaders Mercedes

Horner believes the team's success over the past four years means they cannot be written off so early in the season

Red Bull team principal Christian Horner is adamant Mercedes can still be caught in this year's Formula One world championship.

As Horner himself points out, after six grands prix the dominance of Mercedes has left them only 18 points shy of a maximum score, scoring 240 points from a potential 258.

Five consecutive one-twos have propelled Mercedes into a 141-point lead over Red Bull in the constructors' championship going into Sunday's Canadian Grand Prix, a seemingly insurmountable hurdle even with 13 races remaining.

Horner, though, is convinced all is not lost and that a fifth world title is not beyond his team.

When asked as to what fuelled his belief, Horner replied: "Just looking at what we've achieved over the past four years, the quality of the team we have.

"Nobody is giving up, nobody is chucking in the towel.

"Yeah, we've a mountain to climb, and take nothing away from Mercedes who have done an incredible job this year.

"But as we've seen in previous years, like in 2012 when we had a difficult start, we managed to turn that situation around and get ourselves back into that championship.

"The task here is certainly bigger than that, but nobody is giving up on anything.

"As we saw in Monaco (the last grand prix) we started to put them under a little bit of pressure."

Horner, however, knows after the problems power unit supplier Renault experienced in pre-season, Red Bull have since been playing catch up.

Whilst Red Bull and Renault have made significant strides, being on the back foot has resulted in Mercedes' runaway start to the season.

Dismissing suggestions thoughts are already turning to next year, Horner added: "We're not choosing to look at it like that.

"Obviously Renault have to start thinking about next year because they have to again submit the elements they can change within their design.

"Of course, what they learn this year is absolutely relevant to next year.

"So our focus at the moment is very much on each race as it comes, developing the car as best we can and trying to reduce the gap.

"Renault fully understand the predicament they are in. Carlos Ghosn (CEO) was in Monte Carlo to look and see for himself.

"There are no ultimatums to Renault, other than we want to improve as quickly as we can.

"We've enjoyed a great deal of success with them over the years. All our race victories and world championships have been with Renault engines, and we trust in them to sort out their issues."

It is why Red Bull will not be jumping ship to another power unit supplier, as recent speculation has suggested.

"Not at this point in time," asserted Horner. "One hundred per cent next year we will be powered by a Renault engine."