JetBlue Airways has signed an order for 86 Pratt & Whitney engines to power Airbus A320neo jetliners, the enginemaker said on Wednesday.

The engines, to be delivered beginning in 2018, will power 40 jetliners. The airline will also take six spares. The contract also includes a long-term maintenance agreement, Pratt, a unit of United Technologies , said.

In a statement, JetBlue Chief Executive Dave Barger said the engines will maximize performance and efficiency, while minimizing our carbon footprint.

JetBlue is not disclosing the value of the PW1100G-JM PurePower engine order, spokesman Mateo Lleras said.

The order is expected to be officially announced on Thursday.

(Reporting By John Crawley; Editing by Gary Hill and Richard Chang)