Honda F1 boss Yusuke Hasegawa says Formula 1's 2021 engine proposal is a work in progress and subject to change.
While Ferrari, Mercedes and Renault voiced their - somewhat negative - opinion on the sport's prospective engine rules, Honda had yet to express its view on the draft proposal.
Hasegawa admitted his company's stance was one dictated by discretion and prudence.
"Obviously we have started the discussion with the FIA so I don't think it's a good idea to say yes or no in the public," said the Japanese engineer.
"But of course we are respecting the FIA's decision, as they are trying to create a good competition for Formula 1.
"We are thinking there is some room to modify, so we are trying to find a good solution.
"Obviously the cost reduction is very important and we are welcoming new manufacturers, so from that point of view we would like to keep discussing," Hasegawa added.
Looking back on 2017 and Honda's troubled season - its third - with partner McLaren, Hasegawa conceded the manufacturer's approach to the year had been wrong.
Poor results dissolved led to the dissolution of the McLaren-Honda partnership, with Honda moving its engine supply to Toro Rosso for next season.
"From last year to this year, we completely changed the concept of the engine and tried to do a little bit too much," he admitted.
"That's why we have decided to keep the concept for next year, so that from a reliability point of view we are pretty much confident.
"Now we need to squeeze more performance from the same concept of the engine, which is what we are currently doing."
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
