Ethiopian Airlines would be interested in buying around 10 to 20 of the mid-sized jets that Boeing is studying whether to develop, the African airline's chief executive said on Tuesday.

Boeing is looking at potentially filling a market gap between narrow and wide-body jets with a new aircraft that could seat 220 to 270 passengers.

Ethiopian Chief Executive Tewolde Gebremariam said the airline was interested in a replacement for the out-of-production Boeing 757.

"It is a very right size, and right range for the missions we have, especially (for) the altitude in Addis (Ababa) airport," he told reporters at the Dubai Airshow.

Boeing stopped producing the 757 in 2005, after delivering 1,049 of the jets, known for their powerful engines that allow them to take-off on short runways and can carry 200 passengers in a typical two-class configuration.

Industry sources have said they expect a commercial launch from Boeing of the new mid-sized jet next year. It would enter service in 2024 or 2025 as Boeing attempts to leapfrog the hot-selling Airbus A321neo.

Gebremariam also said Ethiopian would decide next year whether to buy Bombardier's CSeries or Brazil-based Embraer's E-jet series as a replacement for Boeing's 737-7.