OSLO, Jan 13 (Reuters) - Norway's oil and gas firm Equinor is considering selling its onshore shale assets in the Bakken field in the United States, Norwegian business daily Dagens Naeringsliv reported on Wednesday, citing a company executive.

"We have not made a final decision yet. But our intentions are clear. Our whole portfolio is under consideration, including our onshore U.S. portfolio," Equinor's Executive Vice President Al Cook told the daily.

"When we look at Bakken, we must ask ourselves how we create the most value: is it by staying on as an operator, or as a partner or by selling the field," he added.

Equinor's spokesman told Reuters the company was reviewing its whole portfolio, including its assets in the United States, following its chief executive change last year.

The spokesman declined to say whether company has hired any external financial advisers or banks to proceed with the sale process.

Equinor wrote off $2.9 billion in the third-quarter of 2020, including $1.4 billion in the United States, after cutting its long-term oil and gas price forecasts.

The biggest hit came from a $1.38 billion write-off in the United States, most of it from the company's loss-making onshore shale oil and gas business, pushing Equinor to a net loss of $2.12 billion in the third quarter.

(Reporting by Nerijus Adomaitis, Editing by Jane Merriman)