Lewis Hamilton's Mercedes Formula 1 team has been fined €5000, after being referred to the stewards at the Singapore Grand Prix having broken the technical regulations.
A notification from F1 technical delegate Jo Bauer after the opening free practice session said the fuel that Hamilton planned to use was cooler than allowed under the rules.
The notification said: "The temperature of the fuel intended for immediate use in car number 44, measured at 17:44 with FIA approved and sealed sensor, was more than eleven degrees centigrade (20.3) below the ambient temperature recorded by the FIA appointed weather service provider one hour before the first free practice session (32), this not being in compliance with Article 6.5.2 of the 2019 Formula One Technical Regulations.
"I am referring this matter to the stewards for their consideration."
Cooler fuel delivers a performance benefit in terms of power and density.
The FIA enforces a temperature limit to stop teams finding a performance benefit.
Alfa Romeo was also fined €5000 for a similar offence at the Austrian Grand Prix earlier this year after the fuel intended to be put in Antonio Giovinazzi's car was found to be too cold.