Low-cost airline Norwegian Air Shuttle notched up the pressure on Boeing on Friday after the US aerospace giant informed it that its deliveries of the beleaguered 787 Dreamliner could be delayed.
"As one of Boeing's biggest customers in Europe, we expect that the aircraft manufacturer does everything in its power to get the aircraft ready for delivery as soon as possible," the airline's chief executive Bjoern Kjos said in a statement.
With a large fleet of 737s for its short and mid-distance flights, Norwegian ordered eight Boeing 787s for its long-haul routes to New York and Bangkok.
The company said Boeing had informed it of a "possible" delay in the delivery of the first two aircraft, which were initially expected in late April and in June.
As a result, Norwegian plans to lease other planes for a period of up to three months to ensure flights are operated as scheduled.
On January 16, the 50 Dreamliners in service around the world were grounded after two fires linked to its batteries. Two days later, Boeing suspended deliveries of the aircraft until further notice, but continued production.
The US Federal Aviation Authority on Thursday approved Boeing's request to conduct test flights of the Dreamliner in a bid to determine the cause of the burned batteries.
The US National Transportation Safety Board also said Thursday it had pinpointed how a battery caught fire on one of the planes.