A Bombardier CSeries aircraft is pictured during a news conference to announce a partnership between Airbus and Bombardier on the C Series aircraft programme, in Colomiers near Toulouse, France, October 17, 2017. REUTERS/Regis Duvignau

TOULOUSE, France (Reuters) - Airbus AIR.PA will need to increase sales of Bombardier's BBDb.TO CSeries jets to cut production costs, the European planemaker's procurement chief said on Tuesday.

Last year, Airbus agreed to take a majority stake in Bombardier’s CSeries jetliner program, which had not secured a new order for the 110-130 seat plane in the 18 months before the deal.

Their partnership is awaiting regulatory approval and both Bombardier and Airbus have expressed optimism over the CSeries’ long-term sales prospects.

“First we’re going to have to sell the aircraft, in order to then work with suppliers on costs of the program, because at the moment there is a gap,” Klauss Richter told reporters at Airbus’ Toulouse headquarters.

“An increase in productivity rate will help,” he said.

In November, EgyptAir signed an initial order for 12 CSeries jets and Bombardier also received an order for 31 planes from an undisclosed European buyer, marking an end to its sales drought.

Quebec’s Prime Minister Philippe Couillard, also speaking to reporters at Airbus’s Toulouse headquarters, said approval from the regulators was the final hurdle standing in the way of a viable future for the CSeries.

The deal gives the CSeries improved economies of scale and a better sales network.

Bombardier said in February that there had been a “bit of a pause” in orders for its 110-130 seat jets as airlines wait for it to complete the Airbus partnership deal.