Alonso to retire from Formula 1 at end of season

McLaren has been exploring the possibility of working again with Andretti to field an IndyCar team to run the entire series next year or might consider putting together their own team.

Ryan Hunter-Reay, the winner of the 2014 Indy 500 and a teammate of Alonso's with Andretti for the one race, said the Spaniard would be welcomed back and would be a great addition to the series.

"It would be appealing to me if I were him," said Hunter-Reay during a conference call ahead of this weekend's IndyCar race at Pocono.

"I spent time with him as his teammate and know he's as hungry as ever to win.

"We worked very well together and would welcome him no doubt, but I have no idea where this whole thing is going right now.

"I don’t know where McLaren stands with it... a lot of speculation at the moment but I think he would be a great addition to IndyCar and have a lot of fun here."

Alonso thanked Formula One Chief Executive Chase Carey and the sport's owner Liberty Media Corp for trying to get him to change his mind and left the door open on a possible return to the circuit.

"I know (McLaren) will come back stronger and better in the future, and it could be the right moment for me to be back in the series; that would make me really happy," he added.

"I made this decision some months ago, and it was a firm one. Nevertheless, I would like to sincerely thank Chase Carey and Liberty Media for the efforts made to change my mind."