The field, which is located in the northeastern tip of Colombia, had to cut its output to 400 million cubic feet of gas a day, from 700 million cubic feet, Martinez said. "There was a problem during the maintenance, which led to the reduction of production," Martinez told reporters. "I'd expect production to be back at previous levels by Tuesday, hopefully before." The field, which is operated by state-controlled oil company Ecopetrol SA (EC) and U.S.-based Chevron Corp. (CVX), exports about 300 million cubic feet of gas to the Venezuelan state-owned oil company Petroleos de Venezuela SA, or PdVSA. Read more here. Semana International delivers news about Colombia in English. Find more in home.