Mercedes have confirmed all six cars that use their engine are using an upgraded version which is actually superior to that meant to be introduced two weeks ago in Canada.

The German manufacturer delayed the Phase 2 power unit after a quality issue was discovered during testing on the dyno at the team's engine base in Brixworth, believed to be related to the crankshaft area.

As late as Thursday, the drivers were unaware what specification would be installed for Paul Ricard, but now that the engine set to be used for the next seven races has been revealed.

“All six Mercedes-powered cars were fitted with fresh ICE (internal combustion engine), Turbocharger and MGU-H this weekend,” the team said in a tweet.

“Those new components are of an upgraded specification which contains reliability and performance updates.

"While we would have introduced a Phase 2 PU in Canada, this is a Phase 2.1 with some added goodness," it added.

“Thanks to a fantastic effort by the team in Brixworth!"

The "added goodness" would well include some additional power in qualifying mode though estimates only suggested the difference in performance would be around a tenth of a second.

“The new engine feels clean and fresh but we won’t really know its full potential until tomorrow when everyone gets to turn their engines up," Lewis Hamilton commented.

“I’m grateful for the hard work that everyone put into it back in Brixworth. They’ve been pushing so hard to get this engine and do it in the right way.”