The FIA will provide Red Bull and Formula 1's four other manufacturers a detailed breakdown in how it measured the Austrian company's engine above runaway championship leaders Mercedes, sources told ESPN.
The FIA's ranking has formed the basis of what's known as Additional Development and Upgrade Opportunities (ADUO) and has a major impact on the upcoming engine development cycle.
F1's new regulations had the ADUO mechanism in place in order to stop the competitive field being too spread out.
As part of that process, the FIA has ranked Red Bull's internal combustion engine (ICE) ahead of Mercedes, meaning the manufacturer which has won every race of the year so far is due an additional upgrade this year and next outside the cost cap.
Ferrari, Audi and Honda are all understood to be in line for even more upgrades, based on the percentage of performance points they are judged to be behind Red Bull.
Under F1's new engine rules, the ICE this year makes up one half of a near 50-50 split between conventional power and electrical battery elements.
Red Bull became an official engine manufacturer this year as Red Bull Powertrains, a project undertaken at the beginning of the decade in a technical partnership with Ford with the current regulation cycle in mind.
Despite a decent start to life as a manufacturer, Red Bull had been expecting to be granted ADUO upgrades before the rankings were communicated.
The manufacturers were informed of the FIA's rankings ahead of last weekend's Monaco Grand Prix.
Red Bull sporting executive Oliver Mintzlaff and Red Bull F1 team boss Laurent Mekies had a private meeting with FIA president Mohamed Ben Sulayem to express their surprise over the ranking and to seek clarification how it was settled upon.
Sources have told ESPN that the governing body has agreed to review the measurement system it has been using since the Australian Grand Prix -- they have also told Red Bull they would provide all five manufacturers with a detailed breakdown of the measurement criteria within 10 days, which would mean by the middle of next week.
However, sources do not think there is any chance of the ADUO rankings being rectified, given how diligently the FIA has undertaken its measurement process.
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The exact methodology of ranking the performance has been a closely guarded secret until now -- the first ADUO period ran from the start of March until the Canadian Grand Prix and the second runs from now until the end of the Hungarian Grand Prix at the end of July, meaning rivals could be in line for more upgrades should Red Bull's ICE still be deemed the best by the summer break.
Some sources from rival teams suspect Mercedes has not been running its ICE at full power this year in order to benefit from ADUO.
Red Bull has made no secret of the fact it has been surprised by the ranking of its engine given its performance relative to Mercedes so far.
Red Bull driver Isack Hadjar made a joke about this on Thursday, when asked about the rankings: "I mean, I was checking if we won the first six races of the year, you know, and we didn't, so ..."
However, it is important to note that ICE power is not the sole differentiator in terms of performance. This year's engines are a near 50-50 split between ICE and electrical battery elements, while aerodynamic factors also massively impact the competitive order.
Red Bull's car is known to be significantly heavier than some of its rivals, a situation the team hopes to rectify with upgrades planned for its home race in two weeks' time.
It is a strange situation for Red Bull to be in -- on the one hand, the FIA's ranking is an incredible thing, a ringing endorsement of an engine project built from the ground up from the beginning of this decade; one the other, a double-edged sword if rivals are afforded greater leeway with upgrades down the line based on the FIA's measurement metrics.
It comes at a fascinating time for the company's race team, with superstar driver and four-time world champion Max Verstappen's future uncertain beyond this year.
Verstappen has made no secret of the idea of retirement after 2026 given his disillusion with F1's new engine formula, although Mercedes boss Toto Wolff has made no secret of his desire to bring the Dutchman to his team if the right scenario opened up.
It is understood Verstappen has performance-related clauses in his deal which would allow him out of his contract at the end of 2026.
There is a deeper irony to Red Bull's engine being ranked quickest too, given recent events. Red Bull Powertrains was the brainchild of former team boss Christian Horner, who lobbied against a deal with Porsche which would have given the German manufacturer a 50% stake in the team.
Horner convinced Chalerm Yoovidhya, owner of 51% of the energy drinks company, known officially as Red Bull GmbH, that the F1 teams risked giving too much up to an independent engine manufacturer under the 2026 regulations when it could invest in and set up its own project at its Milton Keynes factory in the UK.
Horner also reasoned that Red Bull risked giving up half of the race team, only for Porsche to deliver a bad engine.
Aston Martin's struggle with new engine partner Honda so far this year could well be seen as vindication of that opinion.
Yoovidhya agreed with Horner's assessment, killing the Porsche deal at the eleventh hour in September 2022 and agreeing on the idea of Red Bull building its own engines for this current regulation cycle. The company soon was able to secure a technical partnership with Ford to help with that project.
Horner's role in that decision to nix the Porsche deal is seen by many with knowledge of the recent political turmoil at Red Bull as a major escalation point in the behind-the-scenes tensions Horner had with Mintzlaff, a key architect of the deal.
Mintzlaff and Mark Mateschitz, son of company co-founder and 49% shareholder Dietrich, had grown concerned at the fact that Horner had total control of the race team, a position only strengthened by the company taking its engine programme in-house at his suggestion.
Horner was removed from the company last July after a lengthy political battle behind the scenes.
Under Horner's guidance, Red Bull Powertrains was able to lure considerable talent over from other teams, including from Mercedes High Performance Powertrains (HPP) -- it is believed upwards of 50 staff made the move, while Red Bull Powertrains head Ben Hodgkinson a signing from HPP too.