Adds details from interview, background from paragraphs 3-8

By Shivansh Tiwary

NEW DELHI, June 2 (Reuters) - Ethiopian Airlines is looking to order at least 20 regional or small narrowbody jets as it moves to expand its domestic fleet and replace some ageing aircraft, the airline's chief executive told Reuters on Monday.

"We are evaluating three aircraft models, the E-2 from Embraer EMBR3.SA, the A220 from Airbus AIR.PA, and the 737 MAX 7 from Boeing BA.N," CEO Mesfin Tasew Bekele said in an interview.

The final order quantity will depend on the type chosen, he added. Boeing's 737 MAX 7, which has a larger seating capacity and sits at the bottom of a larger category than the Airbus A220 and Embraer E-2, is yet to be certified.

Africa's largest carrier is experiencing strong travel demand but has been constrained by jet delivery delays and the grounding of some aircraft due to engine shortages stemming from supply chain disruptions.

"We are receiving airplanes from both Boeing and Airbus, but deliveries have been delayed, some by three months, some six months, some more," Bekele said on the sidelines of an annual IATA meeting of global airline leaders.

The company is also in talks with lessors to bring onboard some jets to ease capacity constraints.

The airline is among several facing grounded aircraft due to bottlenecks in engine maintenance plants. Ethiopian has three Boeing 787 widebody jets grounded due to a shortage of Rolls-Royce RR.L engines, with five turboprop aircraft grounded due to a shortage of RTX's Pratt & Whitney engines.

"Normally engines were supposed to be repaired and returned in three months typically, but now it takes six months or even more to get them repaired and returned," Bekele said.

(Reporting by Shivansh Tiwary in New Delhi. Editing by Jamie Freed and Mark Potter)

((Shivansh.Tiwary@thomsonreuters.com; +91 9708363192; X: @Shivansh_19_;))