The CMP platform, designed to cover the small car and the lower part of the compact segment, allows for gasoline, diesel or full-electric power. It was launched last year with the DS 3 Crossback small SUV, and it underpins the new generation of Peugeot 208 and 2008 and the Opel/Vauxhall Corsa. The next model using CMP is expected to be a replacement for the Citroen C4 Cactus compact hatchback, due next year.

The EMP2 platform, covering the upper part of the compact segment up to midsize models, debuted in 2013. Among other models, it is used for the Peugeot 3008 compact crossover, the 5008 midsize SUV, the DS 7 Crossback, the Citroen C5 Aircross and the Opel Grandland. The Peugeot 508 midsize sedan and station wagon, launched last year, also use the architecture. Currently EMP2 is offered with gasoline, diesel and gasoline plug-in hybrid models, but it is also designed to offer pure battery models in the next decade.

The first FCA model based on the CMP architecture could be a small crossover for Alfa Romeo, due in late 2022, also with a battery-only variant.

The Fiat 500e electric model, set to debut in March at the Geneva show and to go on sale next fall, will not be affected by the transition to PSA’s architectures, as it is in an advanced stage of development. It is based on a modified FCA small car architecture and will be built in the Mirafiori plant in Turin.

FCA has said that it will exit the minicar segment and has written off investments in the Mini architecture used in the Fiat 500 and Panda and Lancia Ypsilon. PSA is also likely to leave the segment, with no plans to replace the Citroen C1 and Peugeot 108, now built along with the Toyota Aygo in a jointly owned factory in Kolin, Czech Republic. PSA will leave the joint venture at the end of this year, and Toyota will take full ownership of the plant in 2021

The remaining joint FCA-PSA production of larger models, about 3 million units in 2018, are mainly body-on-frame pickups from Ram (720,000 sales in 2108), and Chrysler and Dodge large sedans, minivans and SUVs (730,000 sales in 2018). Other models on dedicated platforms include the body-on-frame Jeep Wrangler and Gladiator; the Jeep Grand Cherokee, on a unibody platform shared with the Dodge Durango; and commercial vans for Citroen, Fiat and Peugeot. Peugeot is expected to introduce a body-on-frame pickup next year, developed with a Chinese partner.

CORRECTION: An earlier version of this article misstated the year in which PSA's EMP2 platform debuted. It was 2013, not 2017.