Porter Aviation Holdings Inc. is set to announce it will order as many as 30 jetliners from Bombardier Inc. (TSE: BBD.B), marking the first orders of the Learjet maker's recently unveiled C-Series.

The transaction, potentially worth $2.08 billion, could be finalized by Wednesday, according to the Wall Street Journal, which cited sources familiar with the deal.

Montreal-based Bombardier had hinted at the deal back in December, saying an unidentified air carrier in the Americas intended to purchase 12 C-Series aircraft plus options for an additional 18 narrow-body commercial jets.

Porter, based in Toronto, could be looking to fly its new CS100 planes, mid-range craft in the 100-to-149-seat category, to destinations in the U.S. from Montreal and other airports.

Bombardier is preparing to build larger aircraft that can compete with popular models from Boeing Co. (NYSE:BA) and Airbus. Bombardier had seen slow demand for the C-Series planes until this deal with Porter. In November the plane manufacturer pushed back the inaugural flight by six months because of problems with suppliers.

"The CS100's ability to take off and land at around-4,500-foot runways, coupled with a superior noise footprint, makes the C-Series an ideal aircraft for [small Toronto airport] Billy Bishop," said RBC Dominion Securities analyst Walter Spracklin in a late-Monday research note. "However, we believe that significant rework at Billy Bishop, which currently has a runway of 4,000 feet, will have to be completed before the CS100 is able to fly out of the island airport."

Porter's order comes just as British Airways is preparing its own major announcement: BA is set to purchase Airbus jets in a deal worth $7 billion.