MONTREAL (Reuters) - Bombardier Inc BBDb.TO expects its Global 7500 to receive certification from Canada's transport regulator this month, a milestone needed for the plane-and-train maker to begin delivering its flagship business jet to clients, two sources familiar with the matter said.

FILE PHOTO: Bombardier's new Global 7500 business jet is seen during the National Business Aviation Association conference and expo at the Henderson Executive Airport in Henderson, Nevada, U.S., October 8, 2017. REUTERS/David Becker/File Photo

The Global 7500, which is sold out until 2021, is expected to enter service this year and is crucial to Bombardier's turnaround efforts after it sold a majority stake in its CSeries commercial jetliner program to Europe's Airbus AIR.PA.

Montreal-based Bombardier has not disclosed the exact number of orders for the Global 7500, set to challenge U.S rival Gulfstream Aerospace, which has dominated the top end of the market for long-range corporate planes.

“So far, there’s a broad expectation that it will happen by the end of the month, but the decision will be taken by Transport Canada,” said one of the sources on Monday.

Both sources spoke on condition of anonymity because the company’s internal discussions are private.

Regulator Transport Canada, which will make the final decision on the timing of the certification, said by email it could not provide “further details” on Bombardier’s Global 7500 because the information was confidential.

Bombardier spokesman Mark Masluch declined on Monday to comment on expected milestone dates for the Global 7500, but reiterated that the luxury jet was “on track to enter service this year.”

The Global 7500 comes to market as corporate plane makers expect to generate higher revenues during a time of recovering appetite for business jets.

Bombardier, now halfway through a turnaround plan after facing a cash crunch in 2015, is counting on deliveries of the long-range business jet to achieve a 25 percent jump in total company revenues to $20 billion by 2020, compared with 2017. Originally called the Global 7000, the business jet was renamed the Global 7500 in May.

Gulfstream, a division of General Dynamics Corp GD.N, received Federal Aviation Administration certification for its G500 this year and soon expects certification for a second plane, the G600.

Global 7500 would have a range of 7,700 nautical miles, 300 longer than initially expected, and be able to connect far-flung destinations like New York and Hong Kong.