Red Bull chief Christian Horner has said it is “barking mad” to be cutting back on power unit usage with manufacturers having struggled to get through this year with four engines.

But with not all teams in agreement that the rules need changing - and Ferrari president Sergio Marchionne giving short shrift to the idea in the last Strategy Group meeting - there is now no hope of a change.

FIA president Jean Todt said he was as unhappy as other people about the extent that some teams had been hit with grid penalties this year, but added that there was nothing that could be done without all teams agreeing to a change.

“It’s very tough,” said Hasegawa, who was speaking before the news he would no longer be working on the F1 project from January 1, 2018.

“It’s not just for us. Renault had difficulties. I don’t think it’s reasonable. From a technical point of view, it’s difficult.

“If we save the engine performance, it’s easy to achieve. If we use 2000rpm lower, of course we can finish, but there’s no point.”

When asked if the regulation protects Mercedes and Ferrari, Hasegawa said: “As a consequence, yes. We have discussed many times.

“With three engines, it means we only have two chances to introduce a new [upgraded] engine.

“We need to introduce a good engine at the start, but if we don’t, we only have two chances to introduce a new engine.

“Reducing cost is important, so I support cost reduction.”

With engines required to last seven races next year, manufacturers face a difficult balance between pushing for performance and ensuring reliability.

“At this moment, we need to concentrate on reliability, to get an engine to do seven races,” said Hasegawa. “But we need to improve performance too.

“It’s good we have a baseline. We need to confirm the current engine is OK. As soon as we confirm that, we’ll do the next step.”