Boeing Co said on Friday it now expects delivery of the first 787 Dreamliner in the middle of the first quarter 2011, owing to a delay in engine availability.

The delivery date revision of the long-delayed carbon-composite Dreamliner follows an assessment of the availability of an engine needed for the final phases of flight test this fall, Boeing said.

Boeing said it is working closely with Rolls-Royce Group PLC to expedite engine availability. The company said the delay in engine availability has extended delivery date estimate to mid-first quarter 2011.

Boeing had said last month that due to a series of issues, the first delivery of the 787 could be pushed a few weeks into 2011.

The plane maker said on Friday the schedule revision will not affect the company's financial outlook.

However, despite the delay, Boeing said the flight testing across the test fleet continues as planned.

(Reporting by Sakthi Prasad in Bangalore; Editing by Muralikumar Anantharaman)