Alonso's car was pitched into the back of and over the top of Charles Leclerc's Sauber after Hulkenberg hit him from behind when the Renault driver missed his braking point for the La Source hairpin.

In an incident that reminded many people of the start crash that earned a race ban for Romain Grosjean in 2012, Alonso said he was baffled by what Hulkenberg did.

"Yet again a very big-time missed braking point," Alonso told the BBC. "Last time Romain had a race ban. This time we'll see.

"It's hard to understand how you can miss a braking point that much. You arrive at a speed where it's impossible to negotiate the corner."

Images of Leclerc's car appear to indicate that Alonso's car did strike his halo, and Alonso was keen to praise the safety device.

"The positive side is that we all three are okay, including Charles," he said. "I flew over his car and the halo was a very good thing to have today.

"I think for him it helped, looking at the replay. I was definitely happier that I had the halo. We don't need to prove that it's a good thing to have."

Alonso and Hulkenberg have been summoned to see the stewards after the race to discuss the incident.