While Toro Rosso's Franz Tost repeats his call for a freeze on engine development, especially by Mercedes, Red Bull's motorsport advisor Helmut Marko insists that F1 remains an engine formula and therefore the German team remains favourite.

"Let me make something clear," he tells the official F1 website, "from the regulations it’s still an engine Formula, and Mercedes simply has an advantage on that side.

"But we do see our chance this year," he adds, "the simple design of our car, the driveability of the car, our drivers and the stability in the team. Let’s wait and see."

The Austrian admits to being intrigued at how James Allison will fit into the Mercedes picture, the Briton having inherited the W08 from a previous team that included Paddy Lowe.

"James got a pretty well designed car," says Marko. "Now it will be interesting to see how he develops it, because he has to develop a car that is not a product of his philosophy.

"Yes he is an experienced guy, so he will manage it," he adds.

Asked about the RB13, which had a so-so opening test but is expected to come into its own this week, the Austrian enthuses: "We have a beautiful car that is doing very well in fast corners and has good traction. What’s missing is a bit of reliability and power.

"The car as you see it doesn’t have as many flaps and fins as the others," he continues, "so that should help us with the set-up and it gives us a good top speed.

"We have good aerodynamics and not too much drag, and in the end it should also help us in overtaking to have a small and clean car – so that the aerodynamics are working in our favour.

"I am probably not objective, but for me the RB13 is the most elegant car."

A former F1 driver - his career was brought to a premature end after a stone thrown up by Emerson Fittipaldi's Lotus blinded him during the 1972 French Grand Prix - Marko is asked how F1 2017 compares to 'his day'.

"It's a very positive sign," he says. "The cars look far more aggressive. It is really impressive to see how fast they go around corners.

"I am still a bit disappointed about the sound," he admits, "it is not anywhere near the noise that I remember from past times and that was such an important part of the F1 experience for the fans. But hopefully we are getting there as well - step by step."

Asked why the Toro Rosso isn't similar to the Red Bull, he reveals the true state of the relationship between the two teams.

"The Toro Rosso design was more or less the same for the last couple of years," he says. "Now with the rule changes - and because it is our junior team - we wanted to have the car look more aggressive, more young in design and livery.

"The feedback has proved us right," he continues. "Red Bull Racing is another matter, this is the team that has to deliver titles. The junior team can be more of an eye-catcher."

Insisting "we have the strongest driver pairing… period", the Austrian is asked about the expectations of Max Verstappen, who starts his first full season with the team.

"He is more mature," he replies. "It will be his third season in F1, so he must be more consistent and make fewer mistakes.

"We expect both drivers, if the package of car and engine is right, to fight for the championship," he adds, leaving out the bit about; 'because if they don't...

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