The McLaren driver continued with his nightmare season at Sochi and, after reporting problems on the radio before the start, stopped on track before the end of the lap.

It was Alonso's fourth retirement in four races and the second time this season a McLaren has failed to take the start of the race, following Stoffel Vandoorne's DNS in Bahrain.

"It's sad but nothing I can do now," said Alonso. "As soon as we started the formation lap we didn't have the normal power.

"They asked me to change a few things on the steering wheel to try to recover the ERS, but there was no way and at the end of the lap the car stopped. We couldn't even start the race this time.

"I feel bad. We all wanted to be there but these things happen. This is sport. When you are here and you can't race, what can you do? It's not in your hands."

Although Honda suspects Alonso suffered an ERS problem, the Spaniard said they won't know for certain until the engine is analysed.

"Until the car is back in the garage they won't have the answer, but it's a power unit problem," he said.

"Let's hope we can solve them as quickly as possible because we haven't finished a race this year and we couldn't even participate in this one, so there's a few things to improve."

Alonso will now shift his focus to Indianapolis, where he is scheduled to test the Andretti Autosport car this week as part of his preparations for his Indy 500 debut.

"I'll see if I can find an earlier flight but there doesn't appear to be, so I'll watch the race and have an ice cream," Alonso added.