The two-time champion announced earlier this week that he would not be competing in F1 in 2019, but has not ruled out a return in the longer term if the right opportunity came up.

Speaking for the first time on Thursday about the call not to carry on in F1, Alonso said that the predictability of grand prix racing and the lack of excitement proved to be major turn offs for him.

“The action on track is not the one I dreamed of when I joined F1, or when I was in different series, or the action on track that I experienced in other years,” said Alonso ahead of this weekend’s WEC round at Silverstone, where he will be driving for Toyota.

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“I stopped because the action on track in my opinion I feel is very poor. In fact, what we talk about more in F1, is off track. We talk about polemics. We talk about radio messages. We talk about all these things, and when we talk so many times about those things, it is a bad sign. 

“It is because the on-track action was very poor on that weekend, and that is what I feel in F1 now, and I think there are other series that maybe offer better action, more joy and more happiness, so that is what I try to find.”

Although Alonso concedes that a realistic prospect of winning a third world title in 2019 may have been enough to convince him to stay, he is clear that F1 has become something that no longer enthuses him.

“When I was in 2003, 2004, 2008, 2009 and 2011, I was not winning [many] races in those years. But it was difficult to predict [then] what could happen in Spa and Monza. 

“Now, we can write down what is going to happen at Spa and Monza. We can put the first 15 positions with maybe one or two mistakes. So how predictable everything became is tough. 

“We go to Barcelona and we test the first day of winter testing and you know what you will do until November in Abu Dhabi and it is tough. For me, it is not too much of a problem because after 18 years, as I said before, I achieved more than what I dreamed of. 

“But for young drivers or different drivers, it is tough because they just hope that next year the team does an unbelievable step or they receive a call from one or two teams. It became difficult for ambitious drivers.

"[For] a driver with some kind of ambition, it will be tough for the future if things don’t change.”

Door open to F1 return

Alonso only expects to firm up his 2019 plans later this year, with him weighing up options in IndyCar as well as his WEC commitments with Toyota.

But despite not racing in F1 in 2019, he has made clear that a statement suggesting he is open to a return from 2020 is logical because he would be stupid to close off the opportunity now.

“I think the door open is more because I think I am driving at the best level of my career now," he explained. "And why to close doors if anything could happen in the future? 

“I am still young. I am not 45 years old. I feel strong and I am doing this year 27 races, so my thinking is to stop. And that is why I stop. But who knows? That is the reason why.”

Additional reporting by Edd Straw