DOHA: Chevron Corp., Royal Dutch Shell Plc, Total SA, ConocoPhillips and Maersk Oil Qatar submitted bids to operate Qatar’s biggest offshore oilfield, according to two people with knowledge of the matter.

Qatar Petroleum received proposals from the five oil companies to enter a production sharing agreement to operate the Al-Shaheen field, which currently produces 300,000 barrels a day, said the people, who asked not to be identified because the matter is private. State-run Qatar Petroleum will choose an operator this year, they said.

Officials at Chevron, Total, Conoco and Qatar Petroleum didn’t immediately respond to requests for comment. Shell declined to comment, while Maersk referred a request to Qatar Petroleum.

Al-Shaheen accounts for about half of Qatar’s daily crude output and the same share of Maersk’s production. Qatar pumped 670,000 barrels of oil a day in April, data compiled by Bloomberg show. The country, the third-smallest oil producer in the Organisation of Petroleum Exporting Countries, is the world’s biggest exporter of liquefied natural gas. Sales of oil and LNG have made the state of 2.5 million people the world’s richest per capita by purchasing power parity, according to the World Bank.

Maersk Oil Qatar, a unit of Copenhagen-based AP Moeller-Maersk A/S, is the current operator and has developed and managed the field since 1992. Its agreement with Qatar Petroleum ends in mid-2017.