Formula 1 boss Ross Brawn is “optimistic” that the new set of power unit regulations being introduced for 2026 will tempt Honda back into the championship.

The Japanese manufacturer announced it is quitting F1 at the end of next season earlier this month, marking a blow for the series and leaving the Red Bull and AlphaTauri teams seeking a new power unit supplier from 2022.

Brawn admitted he was disappointed by Honda’s decision to leave F1 but believes the new engine regulations will encourage the manufacturer to return.

“It is unfortunate Honda are leaving Formula 1 at the end of 2021," Brawn said in his latest post-race column for the official F1 website. "It's the third time in my racing career they stepped back and came back again.

"I'm optimistic when their situation changes and when F1 evolves, we can engage them again, as Honda have always been important and welcome members of the F1 community in the past and hopefully for the future.

"All automotive companies are facing massive challenges at the moment.

“And we as F1 need to respond to that and make sure F1 meets those challenges, stays relevant and becomes more relevant to provide automotive partners with viable challenges within F1 which can provide support with their objectives away from F1.”

Brawn hinted that the next cycle of power unit regulations - which are set to replace the current V6 hybrid engines - may come earlier than originally planned, adding he is keen for input from manufacturers on the direction of F1’s next engine formula.

"I hope a new power unit formula which will be introduced no later than 2026 will encourage them to come back again,” he explained.

"We'll also be encouraging them to be part of new FIA working groups, which will recommend what sort of power unit we will adopt in the future.

"They have been great partners in F1 and I look forward to working with them in future."