Production on the Trestakk oil and gas field on Haltenbanken in the Norwegian sea has started, operator Equinor said on Tuesday, adding that the project had come in under budget.

Equinor said that, on field start-up, the final costs are expected to be 5 billion Norwegian crowns ($585 million) compared to the 5.5 billion crowns estimated when the project was approved by the authorities in 2017, according to Reuters.

The field has estimated recoverable resources of 76 million barrels of oil, the company added.

Equinor holds a 59.1% stake in the Trestakk licence, while ExxonMobil has 33% and Vaar Energi has 7.9%.