Norwegian Air Shuttle ASA reached an agreement in principle with Boeing Co. for the purchase of 50 737 Max jets, to be delivered when the carrier’s existing leases end.

The airline will take delivery of the planes between 2025 and 2028, according to a stock exchange filing Monday. Norwegian expects to finalize the order, which also includes options for an additional 30 aircraft, by the end of June.

Norwegian has focused on rebuilding its operations as a regional carrier after pivoting away from discount long-haul flights following since emerging from insolvency. The airline plans to make pre-delivery payments for the new Max jets through “positive cash flow from operating activities,” it said.