* State oil company posts 3.69 billion peso loss
* Long term liabilities continue to mount (Adds bullets, byline, dollar values, balance sheet details)
By Robert Campbell
MEXICO CITY, Oct 28 Mexico's state oil monopoly Pemex posted a loss of 3.69 billion pesos ($273 million) in the third quarter, less than the 14.393 billion pesos it lost in the same period a year ago, the company said in a filing with the Mexican stock market on Wednesday.
Pemex [PEMX.UL] said its results improved due to lower taxes and cheaper fuel imports but these positive factors were partially outweighed by reduced volumes of crude oil exports.
Mexican oil production has been trending lower due to the aging of the giant Cantarell oil field.
However, Mexico managed to post stable output in September and officials say they have finally got a grip on the problems at Cantarell that have sent Mexican production down by nearly 25 percent since it peaked in 2004.
Pemex's heavy reliance on debt to finance its capital investment program and its large unfunded pension obligations have sent its long-term liabilities surging.
The company reported long-term debt of 545 billion pesos, up from 446 billion pesos in the third quarter of 2008.
Other long-term liabilities, mostly unfunded labor benefits, were 591 billion pesos, up from 494 billion pesos last year.
Long-term assets totaled 917 billion pesos, some 217 billion pesos less than Pemex's long-term liabilities.
Pemex will hold a conference call on Friday to discuss its quarterly results with its bondholders.
($1 =13.5035 pesos at end-Sept.) (Editing by Christian Wiessner)