Fernando Alonso to miss Monaco Grand Prix to race at Indy 500, no replacement named yet

The Spaniard will still race for his F1 employers McLaren, who are returning to Indianapolis after a 38-year absence.

However, it raises fresh speculation that this will be Alonso’s last season in F1 – even as McLaren insist he is swapping codes with their blessing.

Alonso told McLaren’s official website:

"Of course, [it’s] a regret of mine that I won’t be able to race at Monaco this year. But Monaco will be the only 2017 Grand Prix I’ll be missing, and I’ll be back in the cockpit of the McLaren-Honda MCL32 for the Canadian Grand Prix in Montreal in early June."

The two-time world champion is still awaiting his first podium finish since moving back to McLaren in 2015, with poor pace and reliability issues leaving him a disillusioned figure in the paddock.

He started 2017 with two disappointing finishes, both outside the points, with reports suggesting he could walk away from the sport when his contract expires at the end of the season.

No replacement has yet been named for Alonso. His former team-mate Jenson Button remains on McLaren's books until the end of 2018 but is on a sabbatical in a deal brokered by deposed chairman Ron Dennis last year.

While the 2009 world champion would appear an obvious choice, Brown says no decision has been made on who will partner rookie Stoffel Vandoorne, leaving that to racing director Eric Boullier.

"Fernando's replacement driver is not in place," Brown said.

"Those conversations are ongoing, we have a few different options, we will state who that is when we know.

"Eric, who runs the F1 team, is ultimately responsible for making the recommendation as to what driver should go in the car and he will be here at the weekend so I can save questions for him, he is working on it.

"I wouldn't want to share his conversations he has had with whom."