Fernando Alonso believes it would be “too demanding” for him to tackle a full season of IndyCar next year despite his departure from Formula 1.

Having announced his decision not to race in F1 in 2019, Alonso was heavily linked with an IndyCar seat after his impressive debut at the Indy 500 in 2017. A test at Barber followed in September as McLaren also explored the idea of a full-time entry, but Zak Brown announced on Friday that next year would come too soon.

Alonso insists he made his own decision not to race full-time in IndyCar separately, saying it would take too much commitment to be as competitive as he would like next year.

“In the summertime I was thinking about it, but it was always linked with the team and McLaren,” Alonso said. “We talked a lot at the beginning of the year what the plans were for F1, and I always tried to share my thoughts with the team. Then eventually it came into my mind that it was the time now to stop Formula 1, so they were the first ones to know. At least they had time to make whatever plans they were thinking for the future.

“Then it was the same with IndyCar. I had it in my mind that maybe I could do IndyCar or the Indy 500 or something to plan for next year. They were doing similar observations and thoughts for the future of the team, so we were talking and linked all the time.

“Eventually, one day in my case I thought it was too demanding next year. I don’t know about in the future but next year the commitment of the 17 races, it was too much. That dedication and that amount of work that you need to put into that series to be competitive, starting from zero, I felt it was too much and I shared that with the team.

“When it was (made) public, let’s say it was not a surprise. It may have seemed linked but our two decisions were made independently.”

Despite the decision not to pursue a full-time seat, Alonso says he is still keen to return to the Indy 500 in 2019 to try and add to his Monaco Grand Prix and Le Mans 24 Hour victories.

“It’s a possibility. I would love to do it, to be honest. It’s a race that was magic last year and it still has the biggest for me. Especially now after winning Le Mans, it’s only one step away from the Triple Crown and I would love to do it. I don’t know if it’s going to be next year or in the future but it’s part of the project of next year’s calendar.”