The tension between Mercedes and the other F1 power unit manufacturers and their associated teams has been further increased after the latest round of discussions on an engine 'unfreeze' in 2015 came to nothing.

If we would try to write down who changed his mind when, and how, and why, that would be a long list Toto Wolff

Rivals are incensed that after appearing to agree in meetings in Singapore and again last weekend Mercedes changed its position on allowing an extra window for development in the middle of the season. A unanimous vote is required to bring in changes.

The Stuttgart manufacturer, which has more cars to service next year than any of its rivals, is adamant that attention has to be paid to costs.

Obviously one [player] (Mercedes) does not share these values of F1 Marco Mattiacci

“If we would try to write down who changed his mind when, and how, and why, that would be a long list,” said Toto Wolff when asked by Motorsport.com. “All of us are having a certain opinion, and certain priorities, and all of us are trying to push very hard for the best for the team, and the best for F1. And the last word, it's still under construction.

An unnecessary increase of costs

“We very much believe we can't take any foolish decisions which would increase the costs dramatically for everybody around here. We need to keep that under control. We owe it to the teams that went out of business, and we have to stay reasonable. We are going to resume the discussions when we come back to Europe.”

Meanwhile Ferrari's Marco Mattiacci says it's not over yet: “We discussed it, some of the players keep changing their ideas, but we keep working, we don't give up on a very fundamental principle of F1 – that is innovating, that is competing. Obviously one [player] does not share these values of F1. But I have to say at the same time we must appreciate the fact that everyone is trying to reach a middle ground.