* Brazil Bovespa gains 0.13 pct, Mexico IPC falls 0.94 pct SAO PAULO, Dec 13 (Reuters) - Brazilian stocks posted slight gains on Friday, led by shares of state-controlled firms, though advances were limited by lingering investor caution over the potential tapering of economic stimulus from the U.S. Federal Reserve.
Mexico's IPC index reopened lower after a market holiday on Thursday, while Chile's bourse slipped for the third straight session.
The Fed's bond-buying program has helped support global demand for riskier assets such as Latin American equities, but it is expected to be reduced in scale as the U.S. economic recovery gains steam.
Investors have avoided taking big positions in local shares until after the Fed makes a decision on the program at its next policy-setting meeting, scheduled to take place on Dec. 17 and 18.
Brazil's benchmark Bovespa stock index rose 0.13 percent to 50,186.12, but is on track to close the session with a 1.4 percent weekly loss.
"It was a tough week and the trend is still one of caution," said Pedro Galdi, a broker with SLW Corretora in Sao Paulo. "If (the Fed) cuts stimulus by 10 billion dollars, it's already priced in. Above that, the market could react. If they wait until March, it will rise." Shares of state-run oil company Petroleo Brasileiro SA , known as Petrobras, rose 0.95 percent, contributing most to the index's rise.
State-controlled lender Banco do Brasil SA added 1.4 percent, while private-sector rival Banco Bradesco SA advanced 1.1 percent.
Shares of mining firm Vale SA anchored the index, losing 0.85 percent.
Mexico's IPC index fell for the second straight session, losing 0.94 percent to 41,907.71.
Shares of bottling firm Femsa lost 2.22 percent, contributing most to the index's decline, while telecommunications firm America Movil, controlled by billionaire Carlos Slim, fell 1 percent.
Chile's IPSA index fell 0.31 percent as shares of conglomerate Copec slipped 1.4 percent.
Latin America's key stock indexes at 1524 GMT: Stock indexes Latest daily % YTD % change change MSCI LatAm 3,167.20 0.44 -16.5 Brazil Bovespa 50,186.12 0.13 -17.66 Mexico IPC 41,907.71 -0.94 -4.11 Chile IPSA 3,661.85 -0.31 -14.87 Chile IGPA 18,098.08 -0.24 -14.11 Argentina MerVal 5,240.83 0.33 83.61 Colombia IGBC 13,299.06 0.85 -9.63 Peru IGRA 15,186.92 0.1 -26.38 Venezuela IBC 2,657,078.10 0.1 463.61