Mercedes team principal Toto Wolff has voiced strong opposition to the FIA's proposed mid-season rule change for Formula 1 engines in 2026. The governing body submitted a proposal to close a loophole in the compression ratio regulations after lobbying from rival power unit manufacturers.

Wolff admitted he is 'philosophically' opposed to changing rules during the season but said Mercedes would accept the change to be 'good citizens' in the sport. The proposed alteration would require engines to comply with regulations both when cold and hot, potentially impacting Mercedes' perceived advantage. All four other engine manufacturers must vote for the change alongside the FIA and Formula 1.

Adding to the controversy, Wolff dismissed reports that Mercedes' fuel supplier Petronas faces certification issues for the opening race in Melbourne. 'This is another of these stories,' he said, comparing it to previous claims about illegal compression ratios. 'I can't even comment.' The rule change vote is expected before the Australian Grand Prix on March 8, with testing continuing in Bahrain ahead of the season opener.