"The aircraft will be delivered under the terms of a firm contract which has already been signed," the company, a subsidiary of Airbus Group, said in a statement.

The deal brings the total number of converted Airbus jetliners sold as tankers to 34 after Australia, Britain, Saudi Arabia and the UAE previously placed orders.

India is in the "final stages of contractual negotiations for six aircraft," according to the statement.

(Reporting by Tim Hepher; Editing by James Regan)