DUBLIN, Aug 11 (Reuters) - The head of the world's largest aircraft lessor said recently revised production plans by Airbus still appear "somewhat optimistic", providing a further boost to demand for leasing as the recovery in air travel picks up pace.

AerCap Chief Executive Aengus Kelly said deliveries from both Airbus and rival planemaker Boeing were also being held back by the need to divert scarce engines to their existing fleet to be used as spares.

Airbus last month cut its annual jet delivery forecast and put the brakes on planned production increases, bowing to pressure from fragile supply chains and labour shortages as aerospace struggles to meet resurgent demand. (Reporting by Padraic Halpin, Editing by Tim Hepher)