PSA Peugeot Citroen said its small-car platforms and General Motors' mid-sized car technology would likely underpin the first phase of the automakers' alliance.

Plans to share auto parts and ultimately factories will play to the French car maker's strengths in subcompacts and GM's experience with larger models, Peugeot Chief Executive Philippe Varin told reporters at the Geneva Auto Show on Wednesday.

(Reporting by Laurence Frost; Editing by James Regan)