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By Julia Symmes Cobb and Marianna Parraga
BOGOTA/HOUSTON, April 5 (Reuters) - Colombia's oil regulator said it has postponed the deadline to receive offers for 15 onshore areas at its Sinu-San Jacinto auction until May 3 at the request of the bidding companies.
Colombia is the third Latin American country hosting an oil auction this year after Mexico and Brazil. Its bidding round comes after a four-year pause during which low oil prices stopped many countries in the region from offering their acreage for foreign investment.
The bids had been scheduled to be received on Thursday. The change, announced by the National Hydrocarbons Agency (ANH) late on Wednesday, marks the fifth time the auction for the 15 crude and gas areas in the country's northwest has been rescheduled.
Six companies have qualified for bidding: Canada-based Parex Resources Inc, Gran Tierra Energy Inc, Chinese CNOOC's unit Nexen Petroleum, Colombia's Hocol, Repsol's Talisman Energy, and U.S.-based Noble Energy Inc .
An ANH representative told Reuters on Thursday the companies requested the delay but did not provide further details.
Colombia has invested some $200 million to study the offered areas, ANH president Orlando Velandia said during a business trip to Houston last month.
Velandia has said the Andean country will begin routinely offering onshore and offshore areas for exploration and production in May.
Colombia needs to boost foreign investment to revive its stagnant crude and gas production. The Andean country plans to slightly increase output to 900,000 barrels of oil equivalent per day this year.
Colombia's last oilfield auction in 2014 secured investment from firms including ConocoPhillips and Parex for seven unconventional projects that are about to finish the exploration stage.
State-run company Ecopetrol plans to invest up to $4 billion in 2018, largely in exploration and production. Private firms in the country are expected to invest a further $4.5 billion to $4.9 billion. (Reporting by Julia Symmes Cobb in Bogota and Marianna Parraga in Houston Editing by Jeffrey Benkoe)