The first phase of the $6 billion Sangomar offshore oil field project would develop 230 million barrels, with first oil targeted for early 2023 at a production capacity of 100,000 barrels a day, Woodside said.

ASX-listed Woodside and its joint-venture partners will be able to start construction after the government of Senegal executes the Host Government Agreement and awards and approves key contracts, Woodside said in a statement on Thursday.

The joint-venture partners in the project – Woodside, ASX-listed Far Limited, Capricorn Senegal Limited and Senegal state-owned oil company Petrosen – are eager to press ahead with the project. Financing for the project has faced delays due to an arbitration sought by FAR Limited, which owns a 15 per cent interest in the project. FAR challenged Woodside's acquisition of a 35 per cent holding from ConocoPhillips in 2016.

Woodside on Thursday said the government of Senegal had also approved a proposed plan for the exploitation of oil at three offshore joint-venture projects – Rufisque Offshore, Sangomar Offshore and Sangomar Deep Offshore.

The approval comes as a final investment decision on another major Woodside project, the Scarborough gas field development, also edges closer after the company and its joint-venture partner BHP announced a deal to process gas at Woodside's Pluto LNG facility in November.

Woodside and BHP, which has a 25 per cent stake in the Scarborough field off WA's Pilbara coast, have inked a non-binding agreement that would see BHP make a decision on the project by mid-2020.

Woodside shares were down marginally at $35.85 at midday.