Double F1 world champion Alonso, who was the only McLaren running the team’s latest update package at the Red Bull Ring, was collected when Raikkonen lost control after Turn 2 on the race’s opening lap.

The Ferrari ended up perched atop the McLaren as both went into the barriers.

Honda suspects Alonso’s engine suffered damage in the impact and has elected to change it for Silverstone as a precaution while it conducts further investigations.

Alonso will revert to an old power unit used earlier this season, so he will not incur any grid penalties unless he requires a new unit at some point during the British GP weekend.

Team-mate Jenson Button, who had a 25-place grid penalty in Austria for engine tweaks, also had a sensor issue there, with investigations continuing to decide whether the Briton will need to take further penalties for his home race.

Honda motorsport chief Yasuhisa Arai said: “We have since completed thorough checks of both power units back at the factory.

“We believe that Fernando’s power unit has sustained damage from the accident, and it may be necessary to change the engine.

“As for Jenson’s power unit this weekend, the issue is still under investigation.”

Honda used two tokens of its engine allocation earlier this season, but the Japanese manufacturer has chosen not to use any for Silverstone.

“Honda is not looking to put any hardware updates in place for the British Grand Prix,” Arai said.

“But we will optimise the power unit setting to the updated aero parts planned on the chassis.”