Boeing has planned to undertake the first test flight of its 777X twin-aisle jet slightly later than it had initially planned.

Citing people familiar with the matter, Boeing reported that despite the delay of the first test flight to late June, the company plans to put the aircraft into service by next year.

Boeing expects the new jet will strengthen its presence in the ‘mini-jumbo’ market. In this market, it competes with Airbus SE’s 365-seat A350-1000.

The company expects to secure orders for its new aircraft after the retirement of Airbus’ A380 superjumbo, reported the news agency.

Boeing previously aimed to fly the 777X at the Paris Air Show, which takes place from 17-23 June.

The aircraft’s development has been slowed due to the partial US Government shutdown earlier this year. This shutdown led to assembly delays on its carbon-composite wings and General Electric Co’s new GE9X engines.

Furthermore, Boeing diverted some resources from the programme to concentrate on getting its grounded 737 MAX aircraft back into operation following two crashes, one in Ethiopia and the other in Indonesia.

Boeing had been looking to operate the first flight by 21 June, overlapping with the air show in Le Bourget, Paris, France, according to two people familiar with the matter.

However, the sources added that it may stretch into early July.

The first two 777X flight test aircraft have left Seattle facility and are currently undergoing integrated system testing on the ground.

Two flight test aircraft are currently in the final assembly stage.