The revisions are aimed at reducing costs and delivering more performance parity, and come after months of discussions between four F1's manufacturers.

The changes had been ratified by an E-vote of the F1 Commission earlier today and a statement from the FIA confirmed that they also had the 'support' of F1 supremo Bernie Ecclestone.

In a statement issued by the FIA, it confirmed the outline rules changes that will lead to a reduction in power units to three per season for each driver from 2018.

The new rules

Cost

Agreement has been reached on a significant reduction in the price of power unit supply to customer teams and a reduction in cost to manufacturers over the coming years.

- In 2017 the power unit price for customer teams will be reduced by €1m per season compared to

2016.

- From 2018, the annual supply price will be reduced by a further €3m.

- Cost reduction on power units will be driven by changes to the Sporting and Technical regulations in 2017 and 2018, with a progressive reduction of the number of power unit elements per driver per season.

Supply

Supply of power units to customer teams will be ensured, as the homologation procedure will include an "obligation to supply" that will be activated in the event of a team facing an absence of supply.

Performance convergence

The new agreement includes a package of measures aimed at achieving performance convergence.

- The token system is to be removed from 2017

- Additionally, constraints on power unit part weights, dimensions and materials, and on boost

pressure will be introduced in 2017 and in 2018.

Sound

Manufacturers are currently conducting a promising research programme into further improving the sound of the current power units, with the aim of implementation by 2018 at the latest.