Kia will unveil hybrid concept versions of the Soul and the Ceed at the Paris motor show.
Both cars use a 1.6-litre petrol engine backed up by a 20bhp electric motor.
The motor assists the engine, but the car cannot run on electrical power alone. Both the Soul and the Cee'd use Kias stop-start technology, which it calls Idle Stop & Go, and use a part-time alternator.
As a result, carbon dioxide emissions for the Soul are 117g/km and 114g/km for the Ceed.
There are no immediate plans to sell the cars in Europe, although a 1.4-litre-engined Cee'd will be sold with stop-start from next year. CO2 emissions will be down to 137g/km from 145g/km.