Russian airline S7, formerly called Sibir, has signed a $2.4 billion contract for 15 Boeing 787 "Dreamliner" planes, Russia's Interfax news agency quoted a company statement as saying on Tuesday.
It said the deal also included an option for 10 more Dreamliners.
Last month the company signed a $705 million deal with Boeing , ordering 10 Boeing 737-800s and securing purchase rights for another 10 of the same model.
A spokesman for S7 told Reuters he was unaware that any press release had been issued and declined to make any comment.
S7 is scheduled to hold a news conference later on Tuesday.