Honda discovered a problem with Alonso's MGU-H in Austria and so reverted to a complete old-spec power unit for the remainder of the weekend in the interest of saving time with the change.

For Silverstone, he will go back to the Spec 3 engine that was used on the Friday in Austria, but with the old MGU-H that he ran from final practice at the Red Bull Ring.

A new energy store will also be fitted. As that will be his fifth of the season, he will incur a five-place grid penalty for Sunday's grand prix.

Honda will then take a view as to whether to make further changes after FP2, but the Japanese manufacturer anticipates further changes that will incur more penalties.

Given McLaren-Honda is expected to struggle on Silverstone's high-speed layout, it could tactically take further penalties this weekend rather than at the next race in Hungary, which offers a stronger chance of a good result.

The MGU-H that failed in Austria was a countermeasure part that was drafted in following a string of failures earlier in the season.

Honda sent the part back to its base in Japan and has been working on finding a fix, but with Austria being back-to-back with Silverstone it has been unable to get one ready in time for this weekend.