FILE PHOTO: The Boeing logo is pictured at the Latin American Business Aviation Conference & Exhibition fair (LABACE) at Congonhas Airport in Sao Paulo, Brazil August 14, 2018. Picture taken August 14, 2018. REUTERS/Paulo Whitaker

BRUSSELS (Reuters) - EU antitrust regulators have resumed their investigation into Boeing's BA.N bid to buy the jetmaking arm of Embraer EMBR3.SA, with a decision due by Aug. 7, a European Commission filing showed on Wednesday.

The EU executive halted its probe on Feb. 24 while waiting for the companies to provide information it had requested. The so-called stop the clock ended on April 7, according to the filing. Sources said millions of documents have been provided in recent months.

The EU competition enforcer in October last year expressed concerns about the $4.2 billion deal, saying it would remove Embraer as the third largest global competitor in the highly concentrated commercial aircraft industry, especially in single-aisle commercial planes.

Embraer's commercial unit builds jetliners in the 70- to 150-seat segment and competes with the Canadian-designed A220 programme recently acquired by Europe's Airbus AIR.PA.

Brazil’s competition watchdog has already approved the deal, which has garnered backing from some of the world’s largest aircraft buyers.