The Oslo-based carrier has set up a steering group and appointed financial and legal advisors to oversee the situation following IAG’s bid.
IAG is thought to be positioning itself for talks over a full takeover of the low-cost operator.
The disclosure came as Norwegian announced its first quarter earnings for 2018 on Thursday (April 26).
The airline said it had reduced first quarter losses to 46.2 million NK (£4.18 million) from 1.5 billion NK (£135.4 million) last year.
Meanwhile, its overall operating revenue for the first quarter is up 33% from 5.26 billion NK (£475.1 million) to 6.99 billion NK (£630.9 million).
It also stressed its first quarter results were positively affected by the reclassification of a 1.94 billion NK (£179.4 million) investment in banking group Norwegian Finans Holding.
Norwegian said the first quarter was characterised by “international expansion”, “strong passenger growth” and “higher fuel costs”.
Bjorn Kjos, Norwegian chief executive, said: “In this quarter, we in particular see the effects of higher fuel costs.
“At the same time, we have doubled our fleet of Dreamliners and still manage to fill the aircraft, attracting more customers both in new and more established markets.
“Our long-haul operation is now well established, proving that customers want affordable fares on intercontinental routes.”
Norwegian conveyed 7.5 million passengers in the first quarter, up 12% on last year. Capacity grew 36% and the airline achieved a load factor of 84.5%.
The airline took delivery of six new Boeing 787-9 Dreamliners and two new Boeing 737-800 aircraft during the first quarter.
It started operating flights from Paris to Denver and Oakland/San Francisco, from London to Chicago and Austin, and Rome to Oakland/San Francisco.
However, it will now look to divest up to 140 aircraft through replacement of older planes, as well as sales or leases.
Norwegian also entered into an interline agreement with regional carrier Widerøe during the first quarter.
On IAG’s bid, the airline said in a statement: “Norwegian has received several inquiries following IAG Group´s announcement of its acquisition of 4.6 per cent of the shares in the company.
“The Norwegian board of directors has established a steering committee and engaged financial and judicial advisors to review the situation, handle relevant inquiries and to safeguard the interests of all shareholders.”
