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Rolls-Royce and UTC abandon mid-sized jet engine tie-up

LONDON (Reuters) - British aero engine maker Rolls-Royce (LSE:RR.) and United Technologies Corp (NYS:UTX) have abandoned plans to form a partnership to develop engines for mid-size aircraft, the two firms said on Thursday.

In October 2011 Rolls and UTC, which owns U.S. engine maker Pratt & Whitney, announced plans to form a partnership to develop engines for 120-230 seat passenger aircraft that in future years would replace new, revamped versions of the Airbus (PAR:EAD) A320 and Boeing (NYS:BA) 737 narrow-body planes.

However, on Thursday the two firms said following discussions, they had decided not to proceed with the partnership "because of the current regulatory environment".

"Rolls-Royce remains fully committed to this important market segment and will continue to invest in technologies that will enable us to take advantage of opportunities as they arise," the British company said.

(Reporting by Rhys Jones; editing by Sarah Young)