The framework agreement, the value of which wasn't disclosed, covers ship systems such as the ships' Integrated Platform Management System, main engines and generators.
Also included is "on call" support, on-board technical assistance, spare parts, factory repairs, engineering changes and modifications.
"This framework agreement will serve as a template for a long-term relationship with the Norwegian navy, as the lifetime operating cycle of a ship can exceed 30 years," Navantia said.
"By the end of the year, negotiations will begin on a new long-term agreement, which will include not only maintenance but will also include improvements and developments of the frigates' capabilities in light of new generations of equipment and systems that will come to market during the operational life of the vessels."
Navantia built and delivered five of the Aegis frigates to Norway under a contract signed in 2000.
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