Zak Brown has insisted that Formula 1 will remain Fernando Alonso's "number one priority" in 2018.

The Spanish driver will contest not only Le Mans but other WEC sports car races for Toyota this year, but McLaren executive Brown told Spanish sports daily AS that Alonso will not miss any grands prix.

"His priority is Formula 1, so we are open to other racing activities provided that Formula 1, which is his number one priority, is not compromised in any way," he said.

Alonso missed Monaco for the Indy 500 last year, but the big difference in 2018 is that McLaren is now expecting to field a much more competitive Renault-powered car.

"Everything is going really well with the design of the car," Brown revealed.

"We just passed the crash test and everything has gone according to plan. We are going to present the car on February 23 and be on track for the first time on February 26.

"All the simulations put us where we wanted to be last year. Sometimes the simulations don't work when you go to the track, but last year it worked more often than not so I think we're going to have a solid season."

The 2018 season gets underway with the Australian Grand Prix on March 25.