"These F1 world champions, whether it's Michael Schumacher or Mika Hakkinen, who came close to a comeback, don't want to be too far from the F1 pit lane.

"There's a lot he can contribute experience-wise. Carlos and Lando are open to any ideas that will bring us experience. Fernando knows the team very well, Lando doesn't have that experience, and Carlos doesn't have that experience with us. It's something I'll be talking to him about.

"I'll go to Daytona for Fernando's Daytona testing and we're going to chat to him further then."

Brown said Alonso's exact contribution would be defined as part of McLaren's wider testing programme, which would be discussed with sporting director Gil de Ferran in the coming months.

The team is required to field a young driver for two of the four in-season test days in 2019 - a role that has been filled by Norris for the past two years - but is yet to formally name a reserve driver for next year.

"[I'm] ultimately working with Gil to decide what he thinks is the best driver testing programme for next year, as it's not only Fernando, but we have rookie tests, we have tyre tests, and we have reserve drivers that we need to consider," Brown said.

"So Gil is putting together the ultimate driver-race-testing programme, and we'll make a decision in early January."

McLaren currently has junior drivers Sergio Sette Camara and Nyck de Vries on its books, both of whom will race in Formula 2 next year.