Lando Norris, left, will drive Fernando Alonso's McLaren in first practice on Friday. File photo: John Raoux / AP

Woking, Surrey - McLaren's Formula One reserve driver Lando Norris will make his Friday practice debut at this week's Belgian Grand Prix.

The team said on Monday the 18-year-old Briton will take former double world champion Fernando Alonso's car for the first session at Spa-Francorchamps. Norris is also competing in the Formula Two championship, where he is second overall and 12 points off the lead, with practice for that series starting 25 minutes after the end of the Formula One session.

Alonso has announced he will leave Formula One at the end of the 2018 season and will be replaced by fellow-Spaniard Carlos Sainz in 2019.

Norris could take the place of Belgian Stoffel Vandoorne in the 2019 line-up but the jury is still out on whether he is ready for Formula One and giving him a couple of practice sessions will help clarify the situation.

Friday's practice session will also be a useful comparison with Vandoorne, who arrived in Formula One after a dominant GP2 (now Formula Two) campaign but has so far failed to live up to his promise. Norris tested for McLaren in Hungary before the August break.

McLaren Sporting Director Gil de Ferran in a team preview of Sunday's race at Spa: "This is not only part of his ongoing development, but also the evaluation and performance evolution of the car. We’ll be taking a strategic view race-by-race at where else this might be beneficial for us over the coming Grands Prix."