Fernando Alonso has admitted he could return to formula one in 2020.

During his visit to the Circuit de Catalunya for pre-season testing, McLaren announced that the former team driver will be an 'ambassador' this year.

Alonso will also drive "at selected tests", the team revealed.

"I will be a link between the drivers and the engineers," Alonso explained.

However, contrary to speculation, Alonso ruled out driving the 2019 car before Melbourne.

"At the moment every lap for Sainz and Norris is precious," he insisted.

But Alonso said he might "sit in the car" later in the season, whilst also attending about half of the 21 grands prix.

"Mostly in the second half of the season," he said. "Over the next few months, the Indy 500 and my WEC programme will have priority."

However, the 37-year-old insists he has not 'retired' from F1.

"I was at the top of my game last year," he said. "It would be a waste to stop now.

"That's why I want to do some of the most famous races before looking again at formula one.

"If I have another chance to drive a competitive car, I want to be ready. And that wouldn't work if I'm sitting on the couch at home."

In view of a 2020 comeback, Alonso's new role does make sense. He said that simply by listening to Carlos Sainz and Lando Norris, "I can judge which of the weaknesses of last year's car were ironed out and which were not".

"I do not have to sit in the car myself for that."