The FIA has confirmed Mercedes and Porsche among the 11 Formula E manufacturers that have been homologated for the electric series' 2019/20 season.
The two automotive giants announced they would enter the sixth FE season in July last year, and now the governing body has accepted their applications to produce powertrains.
Mercedes and Porsche join existing FE manufacturers Audi, DS, Jaguar, Mahindra, NIO, Penske and Venturi on the season six list, along with Nissan - which takes over Renault's slot - and BMW joining for season five.
The two season six additions have been given a two-year homologation period by the FIA before the next rules cycle begins for the 2021/22 season.
The remaining manufacturers have a three-year homologation phase, which includes the 2018/19 season that will be the first to feature the new Gen2 FE car.
"I'm delighted to see both Mercedes-Benz and Porsche alongside some of the existing names on the official list of homologated manufacturers for season six," said FE CEO Alejandro Agag.
"We continue to exceed all of the initial expectations set out when we started this journey just four years ago.
"If you had said to me then that we would be in double figures in terms of recognisable names in the world of motorsport - [the] biggest road car manufacturers and automotive brands - I would have said you were crazy.
"But this is the reality now.
"Combine this with the ever-growing list of partners joining the electric racing revolution and it's clear that the ABB FIA Formula E Championship is a very exciting place to be in motorsport."
FIA president Jean Todt added: "The future landscape of the ABB FIA Formula E Championship is growing more and more, and today as we confirm two additional manufacturers for the sixth season we have more evidence of the success of this concept.
"Mercedes-Benz and Porsche are both brands with long and decorated histories in motorsport, and the level of all of the 11 manufacturers that will take to the track from 2019/20 is very high.
"Formula E is going from strength to strength, and the commitment of manufacturers to sustainable racing technology is very encouraging."
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