Boeing Co. formally launched a freighter version of its 777X jetliner as Qatar Airways struck one of the largest cargo deals on record, giving the U.S. plane-maker an edge over longtime rival Airbus SE.

The Doha-based carrier placed a firm order for 34 of the 777-8 freighters plus options for an additional 16 jets, the companies said Monday. That total includes 20 jets converted from a previous order for a passenger version of the 777X. The outlines of the deal were first reported by Bloomberg last week.

Qatar also agreed to take 25 of the largest version of Boeing¡¯s 737 Max narrowbody jet, with options for another 25 of the workhorse aircraft.