Renault kangoo stalls when cold ?

Starts ok runs fine new plugs fitted last week coils ok. It is a 1.6 16v Automatic when you go to move off it stalls, will start ok again but same thing will happen when you come to move off. but when engine is warmed up all is OK. some times you can drive but it will stall till engine is warmed up. Gearbox or engine? any ideas would be appreciated.