Mariani was recruited over an eight-month period through 2023 and took on her role in December of that year.
The FIA statement said that the decision to remove her role had been taken “following a period of review”.
Villareal said that by “connecting more closely with our members on topics such as sustainable fuel, smart cities, and diversity in sport, we can achieve a bigger impact”.
The statement did not explain how this would be achieved by moving sustainability under the umbrella of mobility. The FIA is split into two areas – mobility, which is to do with road transport, and motorsport.
Malhame said in the statement: “The FIA is committed to advancing opportunities for women within the organisation, and across mobility and motorsport… and are proud that 32% of our workforce are women in a male-dominated industry.”
A spokesperson added: “Of the almost 100 women working at the FIA, nearly half (47%) of those are in senior positions.
“Examples include Emilia Abel, who runs global road sport, and Rebecca Lee, head of single-seater operations and the FIA’s first female official F1 starter.”
Mariani is the second major FIA figure to leave this year, following the resignation of the deputy president for sport, Robert Reid, in April.
And it marks the continuation of a trend under the presidency of Mohammed Ben Sulayem, who is running for re-election this year and is so far unopposed.
In the past year, Sulayem has sacked the FIA’s head of compliance Paolo Basarri, the head of the audit committee Bertrand Badre and committee member Tom Purves, the FIA’s chief executive officer Natalie Robyn, F1 race director Niels Wittich, senior F1 steward Tim Mayer and deputy Formula 2 race director Janette Tan.
These departures come against the backdrop of a series of changes to the FIA statutes introduced by Sulayem, which critics say reduce accountability and good governance and enhance the president’s authority.
The latest changes, voted through at last week’s FIA General Assembly with a huge majority, were characterised by one opponent as being an example of a “dark period of democratic backsliding”.
Sulayem has been the centre of a series of controversies since he was elected, including the emergence of misogynistic remarks on a historic website.
In seeking to justify those remarks in December 2023, external, Sulayem pointed to his setting up of the FIA’s commission for equality, diversity and inclusion as evidence of a strong track record on the subject.
He also mentioned that he had been the first president to appoint a female CEO. Robyn lasted the same period of time in her role as did Mariani.