BUENOS AIRES, Nov 27 (Reuters) - Argentine stocks fell for a second consecutive day on Tuesday, dragged down by a global selloff in oil, copper and other commodities while government debt had a mixed session due to doubts about the U.S. economy.
The MerVal index .MERV of 25 leading stocks slid 0.96 percent to 2,169.78 points. Volume was moderate at $53.7 million. Of active issues, 42 rose, 77 fell and 11 were unchanged.
Among the session's value leaders was the Buenos Aires-listed stock of Brazil's state oil company Petrobras (APBR.BA), which slumped 3.27 percent to 148 pesos. Petrobras is weighted as 3.97 percent of the MerVal.
"The MerVal fell again, dragged down by the big fall in commodities that happened after the bad consumer confidence data in the United States," said Claudio Szlaien, an analyst with Marlon Recursos Financieros in Buenos Aires.
In the United States the Conference Board said its consumer confidence index fell to its lowest in two years, and oil prices CLc1 fell by more than 2 percent partly due to concerns U.S. economic problems will grind down demand growth.
Bond prices in Argentina were mixed, with the dollar-denominated Par rising 1.2 percent, and the Boden 14 in pesos down 4.1 percent in over-the-counter selling.
"The price peaks mean that there are different opinions out there: some believe that the U.S. mortgage crisis will get deeper and others believe it will slowly soften," said a bank trader.
In the foreign exchange market, the peso weakened as big companies bought dollars to balance books at the end of the month.
In informal trade between foreign exchange houses, as measured by Reuters, the peso slipped 0.16 percent to 3.1675/3.1700 per U.S. dollar ARSB=. In formal interbank trade, where the central bank intervenes, the peso gave up 0.24 percent to 3.1500/3.1525 per dollar ARS=RASL. (Reporting by Jorge Otaola and Walter Bianchi; Writing by Fiona Ortiz; Editing by James Dalgleish)