Cyril Abiteboul has admitted he is a distant and nervous spectator of the Indianapolis 500 this month.

As practice kicked off at the fabled Indianapolis Motor Speedway in the past days, Alonso admitted that returning in 2021 and 2022 will be "impossible".

"I would have to miss a F1 qualifying if I wanted to do it and next year I won't be with McLaren," said the Spaniard.

Indeed, Alonso had already agreed to contest the famous American oval race's 2020 edition prior to signing up for his F1 return with Renault in 2021.

In Indy practice this week, the 39-year-old then became the first 2020 contender to crash, and afterwards got the all-clear at the medical centre.

But his 2021 boss, Renault chief Abiteboul, is not yet heaving a sigh of relief, as the Frenchman confirms that Alonso will not be at next year's Indy 500.

"No, no, no," Abiteboul said in Barcelona.

"The very straightforward answer is that I'm hardly breathing until next weekend when he steps out of his racing car in Indianapolis," he added.

"I can be very clear that once he is with us that is for good and for a while - so no distraction," Abiteboul added.

Alonso confirms that he will turn his full attention to Formula 1 once he sees the chequered flag next weekend.

"From Monday the 24th, I will prepare myself mentally and physically for the next calendar year," he announced.

"There are some simulator tests that are planned at Renault, and maybe I will visit two or three grands prix just to see how things are going at the circuit," said Alonso.