Fiat on Wednesday unveiled a sweeping five-year overhaul of Chrysler centred on collaboration between the Turin and Detroit carmakers on everything from car and engine designs to procurement and international distribution.

Under the strategy, more than half of Chrysler, Dodge and Jeep vehicles will be built on Fiat platforms by 2014. The share of small and midsize vehicles in Chrysler’s portfolio will grow from 45 per cent to 58 per cent.