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MEXICO CITY, Feb 23 (Reuters) - Mexican conglomerate Alfa on Monday reported a net loss of 6.59 billion pesos ($447 million) in the fourth quarter, hit by the peso's decline against the dollar and a drop in the value of its stake in Canada's Pacific Rubiales Energy Corp.
In the same period a year earlier, the company, which controls petrochemical, car parts and refrigerated foods businesses, made a net profit of 1.03 billion pesos.
Revenue and operating profit rose, but financial costs soared to more than ten times the year-earlier figure, pushing the company to a loss.
Tumbling oil prices have slammed Mexico's peso , which slumped nearly 12 percent against the dollar in the fourth quarter.
The company's debt increased by $1.65 billion to $5.12 billion in the year to end-December, principally to finance acquisitions.
In August, Alfa paid about $173 million to increase its total stake in Canada's Pacific Rubiales to a little over 17 percent.
The company said at the time that the increased stake in Pacific Rubiales, Colombia's second-biggest crude producer, was part of Alfa's long-term strategy to diversify its energy-sector assets.
Reporting by Christine Murray; Editing by Meredith Mazzilli