Formula 1 will increase race fuel allowance in 2019 to allow teams "to use the engine at full power at all times" and make grand prix racing less conservative.
An increase from 105kg to 110kg, agreed in today's Strategy Group meeting in Paris and set to be ratified by the World Motor Sport Council, will be welcomed by the teams.
They have faced increased fuel consumption due to the higher downforce levels and faster lap times generated by last year's aero changes, which have put an extra emphasis on fuel saving in races, something that is not popular with fans.
Other changes for next season are the separation of the weight of the driver and car - with an 80kg minimum for the driver - and the use of biometric gloves for safety reasons.
As reported by Autosport there was further debate on aerodynamic changes for 2019 to facilitate overtaking, and the FIA stressed that it wants a decision by the end of this month.
The governing body noted that "discussions will continue on proposals relating to aerodynamics, with a view to taking a decision by the end of April, once research being conducted by the FIA, in consultation with the teams, has been concluded."
The FIA also presented the latest version of its 2021 power unit regulations, noting only that the engine would be a 1.6-litre V6 turbo hybrid, with no MGU-H.
This format was first outlined, with much more detail, on October 31 last year.
It remains the subject of debate, with sources indicating that the FIA and Liberty have different views on some aspects of the final package.
The FIA said that its technical department "will now meet with current and potential power unit manufacturers to discuss in more detail, with a view to concluding the 2021 regulations by the end of May".
This is the rulemakers' first public acknowledgement of the May deadline for finalising the 2021 power unit regulations since Ferrari boss Maurizio Arrivabene revealed it last week.