Theories are arising over the reason Fernando Alonso pulled in to retire during the Belgian Grand Prix, as Honda confirm no issue with his power unit was found.

The Spaniard blamed an engine problem for his eighth failure to see the chequered flag this season, however, had become frustrated once again by what he called the "embarrassing" performance of the Honda unit as he slipped from seventh place back to 11th in the early laps having moved up from 10th on the grid. 

Expectations had been low heading into the weekend, given the power demands around Spa-Francorchamps, and though a good qualifying and great start had given some optimism, the double world champion called the race "normal" expecting more of the same in Monza.

“We knew Hungary would be a good track good us and we ended up in 6th place, our best result of the season," he said. "Here and next weekend the normal is to be out of the points, but we have to keep on working and improving the car so that once we get to Singapore we’ll have better chances to score points.

“Today was normal and next week will be the same or worse but we keep trying new parts, some already for 2018, so there’s very important work going behind the scenes. All we need is one change…,” he added, clearly referring to the engine.

Honda F1 chief Yusuke Hasegawa acknowledged the decision to retire was precautionary after Alonso reported a problem although there was "nothing showing in the data" to suggest as such. 

Talking to Sky Sports, the 36-year-old was asked if McLaren retaining Honda would signal his exit from the team, after stating it could be post-season before his future is decided.

"We will see what happens in the next couple of weekends. McLaren is always one of the best teams in the world and I would be happy to keep working with them but we need to see how things evolve in the next couple of weeks," he replied. 

However, speaking elsewhere he has admitted to numerous offers for next year, the most recent coming from Williams who would like him alongside Lance Stroll next season.

“I think the stock value has never been as high as now, at least with the offers that I've had, so it's good,” he commented. “We will consider all the options out there. We did a fantastic qualifying, we did a fantastic start, we’ve won a lot of Grand Prix, a lot of things in our career, we shouldn’t be this further back.

“The team is working a lot, I know the guys have been sleeping very little this weekend, so thank you for all that effort and hopefully next weekend we’ll be more competitive.”