The European Commission has opened an investigation into the planned merger of two of the world's major aircraft manufacturers, US Boeing and Brazil's Embraer, concerned it could threaten competition on price and product development, dpa reported. Boeing would take over Embraer's global commercial aircraft business under the plan, potentially reducing the number of competitors in an already concentrated global market, the EU executive - which acts as the bloc's competition watchdog - said Friday. This could make it harder for new entrants to the market, such as those from China, Japan and Russia, the commission added. At present, Embraer and Boeing are competitors in some of the same sectors of the commercial aircraft market, the commission notes. The planned deal, agreed by the two companies at the end of last year, had met with some criticism in Brazil: Embraer also makes military aircraft and is involved in the development of security technology. The commission can open an investigation into companies with a turnover above a certain threshold if it believes a merger would be a threat to competition in the European Economic Area.