(Reuters) - Boeing Co <BA.N> said on Friday it would not make the planned first delivery of its 747-8 Freighter to Cargolux <CLUX.UL> on Monday, citing "unresolved issues" with the airline.

The plane-maker, which had planned three days of celebrations to mark the long-awaited first delivery, did not disclose the problem and referred questions to the customer.

Boeing said it was working with Cargolux to resolve the issues and to set delivery dates for the airplanes. A spokesman declined to say how the snag would affect the 747-8F delivery schedule.

(Reporting by Kyle Peterson in Chicago; Editing by Phil Berlowitz)