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MEXICO CITY, Nov 20 (Reuters) - Mexican oil production increased slightly in October from the previous month, lending credence to the government's argument that a steep decline in output appears to be stabilizing.

Mexico produced 2.602 million barrels per day of crude oil in October, state oil monopoly Pemex said on Friday.

That was a decline of 5.6 percent from a year earlier but was a hair above the 2.599 million bpd produced in September. It was the second straight month showing a slight increase.

Mexican oil production is down by about a quarter from a 2004 peak because its once-largest field, Cantarell, is declining.

Energy Minister Georgina Kessel told Reuters in an interview in October that she was confident Mexican oil production would not fall below 2.5 million bpd over the coming years as a rapid decline in yields at the aging Cantarell field had slowed. [ID:nN20464082]

In October, Cantarell's output fell to 638,979 bpd from 642,371 bpd in September. Production in the Chicontepec field fell to 29,755 bpd from 29,907 bpd in September.

Pemex [PEMX.UL] said total oil exports averaged 1.238 million bpd in October, down 13.7 percent from a year earlier. Gasoline imports fell to 523,800 bpd in October from 413,200 bpd a year earlier.

Mexico produced an average 2.607 million barrels per day of crude oil over the first 10 months of 2009, down 7.1 percent from the same period last year. Exports averaged 1.22 million bpd over the same period, down 13 percent from a year ago. (Reporting by Jason Lange; Editing by Walter Bagley)