** Shares of Boeing BA.N down nearly 2% at $211 and Spirit Aerosystems SPR.N fall nearly 1% to $38 in early trade
** Britains competition regulator on Monday started a Phase 1 investigation into BA's planned acquisition of Spirit Aerosystems, setting a deadline of Aug 28 for a decision
** The Competition and Markets Authority (CMA) said last week that it was considering an investigation as they want to assess whether the deal could harm competition in the UK or other markets
** Last year, Boeing agreed to buy back Spirit in a $4.7 bln all-stock deal, years after spinning off the key supplier
** Including session moves shares of Boeing up 19.1% YTD and Spirit Aero up 12.8% YTD
(Reporting by Apratim Sarkar)
((Apratim.Sarkar@thomsonreuters.com))