The man in charge of Honda’s Formula 1 engine programme has dismissed suggestions its latest spec engine is more powerful.

Red Bull has enjoyed a straightline speed advantage over Mercedes in recent races, most notably since the French Grand Prix.

It was a race won by Max Verstappen on an aggressive two-stop strategy which necessitated his chasing down and passing of Lewis Hamilton.

That coincided with the introduction of a new specification Honda powerunit.

“It’s not true,” Toyoharu Tanabe, Honda F1 Technical Director, said of suggestions the latest spec is more powerful.

“Under current regulations, any performance update is not allowed to apply during the season.

“As a result, our second PU is the same as the first PU in terms of specification and performance.”

This year’s regulations governing powerunits limit what can be done, with any change in specification having to be for reliability or logistical reasons.

“Under the current PU regulations, we need to submit any changes, so, only allowed to change for reliability, cost reasons and logistics,” Tanabe explained.

“Then we need to submit very detail to the FIA first and the FIA approve the changes, FIA distribute documents to the other PU manufacturers.

“We need to have approval from other PU manufacturers to change any single part’s specification, so we are very careful to change the performance,” he added.

It has been suggested that tweaks to the Honda powerunit have allowed it to run at higher power modes for longer, and addressed issues which saw its performance turned down following reliability concerns during pre-season testing.

That is not the case, with Tanabe suggesting the gains this season have been a result of an improved understanding.

“We have been learning gradually how to use the PU,” he said.

“We improve our weakness, and then we push our strengths.

“As a result, the base specification, the performance is the same, but trackside performance I believe we have been improving.”

Though Honda currently heads the world championship courtesy of Red Bull, the company is set to step away from the sport at the end of the season.

However, it will continue to have an involvement, with its facilities set to produce the engines which propel Red Bull and AlphaTauri next season.

Despite that, there is no interest in the Japanese brand reversing its decision to depart, even should it claim the world championship.

“Regardless [of] the result of this year’s championship, or our result, I think Honda’s decision will not change from the previous one, which means leaving Formula 1.”

Red Bull holds a 40-point advantage over Mercedes in the constructors’ title heading into this weekend’s Austrian Grand Prix, the ninth round of the 2021 season.