Mercedes was comprehensively beaten by Red Bull last time out at the Styrian Grand Prix as Max Verstappen finished over 35 seconds clear of Lewis Hamilton.

After the race, Toto Wolff confirmed Mercedes would not be upgrading its car for the rest of the season, stating it was fully focused on the 2022 regulations.

Speaking to the F1 Nation Podcast, Allison - who is Mercedes’ technical director - said that Mercedes will upgrade its car in 2021.

“We have a reasonable number of things that are going to make our car faster in the coming races, and let's hope they prove sufficient,” Allison said.

He dismissed suggestions that his comments were at odds with Wolff’s aforementioned ones.

“I don't think those two things are at odds with each other. And I don’t think Toto has said precisely that,” Allison added.

“What Toto points out is that next year's rules are a big and hairy affair, and that they demand a huge amount of our attention. So most of the focus of our factory has switched over to next year, the performance discovery for next year.

“But that doesn't mean that there aren't things still in the food-chain from prior to that focus switch. And furthermore, it isn't all of the factory. And furthermore, we're only one of two factories, there's also the PU factory and there is a little bit more to come also from the PU.

“So there's some more aerodynamic change in the offing. A little bit on the PU, we hope, on the delivery side, and just a few things that are not quite as tidy as we would wish, that we still have got the opportunity to put right while this season is still very much alive and hot.”

Allison admitted that the changes to the floor area ahead of the season have made it difficult for Mercedes to find gains during the season.

“Ever since the rule changes that were introduced aerodynamically for looking after the tyres, we have found it hellishly hard to find the sort of performance gain rate that we did previously prior to those rules," Allison explained. "So that has made our life trickier than we wished it to be.”