Red Bull is not letting out the secret about a new pair of distinctive 'nostrils' on the nose of its 2020 car.

"It's to make sure Max (Verstappen) is cool enough," Dr Helmut Marko joked to Auto Bild.

But when pressed for an explanation about what designer Adrian Newey has in mind for all the openings at the front of the car, Marko added: "We'd rather keep that to ourselves.

"Apart from that, we all know that we won't see the real cars before the second week of testing," the top team official added.

Verstappen was on duty this week as the RB16 was shaken down at Silverstone, and Marko said "everything went according to plan". Dutchman Verstappen said it was a "very positive" debut for the Honda-powered car.

Ferrari is also hinting at having some "extreme" solutions under the skin of its 2020 car, with Sebastian Vettel commenting: "Sooner or later all the tricks will come out."