The FIA has convened a crucial gathering with Formula 1 power unit manufacturers for 22 January, just days before pre-season testing commences at Barcelona.
The meeting comes amid mounting tensions over allegations that Mercedes and Red Bull have independently devised methods to circumvent compression ratio limits in the forthcoming 2026 engine regulations.
Both manufacturers stand accused of exploiting a potential loophole that would grant them a significant performance advantage over their rivals.
The controversy centres on the new rulebook's stipulation that engines must not exceed a 16:1 compression ratio—a reduction from the previous 18:1 limit introduced partly to assist newcomers entering the sport.
Red Bull have come under fire for finding a loophole in the rules
| GETTYReports suggest that whilst both teams' engines comply with the mandated ratio during static testing at ambient temperatures, the designs allegedly achieve ratios as high as 18:1 once the units reach operating temperatures.
The compression ratio—essentially the relationship between cylinder volume when pistons sit at their lowest versus highest positions—directly influences power output.
The FIA have revealed a statement after an emergency meeting was scheduled
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Higher ratios translate to greater horsepower and improved fuel efficiency.
According to some estimates, the advantage could be worth approximately 15 brake horsepower, potentially equating to three-tenths of a second per lap at circuits such as Melbourne's Albert Park.
The current FIA testing protocol, as outlined in Article C5.4.3, measures compression solely under static conditions at ambient temperature.
Ferrari, Honda and Audi have lodged formal complaints with the governing body, arguing that the approach violates the spirit of the 2026 regulations.
The Italian manufacturer, which supplies power units to Haas and the incoming Cadillac outfit, has been particularly vocal in demanding swift action.
According to reports, the three disgruntled manufacturers penned a letter to the FIA seeking clarification on the matter.
Ferrari, Honda and Audi have lodged complaints amid concerns over Mercedes and Red Bull
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The governing body had initially given its blessing to Mercedes' interpretation after receiving a briefing on the design.
However, that position has come under considerable scrutiny following the formal objections, with rivals pushing for the engine to be prohibited as early as possible.
The FIA has sought to downplay suggestions that the gathering represents an emergency intervention, with a spokesperson stating: "As is customary with the introduction of new regulations, discussions on the 2026 iteration covering power unit and chassis are ongoing."
The governing body emphasised that "the meeting planned for 22 January is between technical experts" and that it "assesses the situation in order to make sure the Regulations are understood and applied in the same manner between all the participants."
Any substantive amendments to the regulations appear unlikely before the summer break at the earliest, with changes more probably targeted at the 2027 campaign.