* Brazil's Bovespa falls 1.56 pct, Mexico's IPC up 0.13 pct
MEXICO CITY, Nov 26 (Reuters) - Brazilian state-run oil firm Petrobras fell to its lowest level in more than a year on Tuesday, pushing the country's stock market to a near three-month low on concerns the government may delay a new pricing policy that could stem losses in the firm's refining division.
Brazil's benchmark Bovespa stock index fell for the fourth session in five, losing 1.56 percent to close at 51,446.91, a level it has not closed below since Aug. 30.
Preferred shares of Petroleo Brasileiro SA tumbled 6.29 percent, their biggest daily loss since June 2012, after Finance Minister Guido Mantega said the government must carefully analyze a potential fuel price policy that would automatically raise gasoline prices along with inflation.
The company has been forced to import fuel and sell gasoline at a loss due to prices that are kept below global market rates to help keep inflation in check.
"People were expecting something to happen on (the pricing formula) this year," said Ariovaldo Santos, a trader with H.Commcor in Sao Paulo. "Mantega came out saying it can't be inflationary or add to indexation of the economy, so now there's an expectation that perhaps nothing will come of it."
Petrobras is the heaviest-weighted component of the Bovespa.
Chile's bourse fell for the fifth session in six, to its lowest close in over two months, dragged down by shares of Latam Airlines and industrial conglomerate Empresas Copec.
Latam Airlines shares dropped 2.43 percent while Empresas Copec shed 1.31 percent, after reporting lower-than-expected third-quarter profit on Friday, contributing to the bourse's 1.24 percent loss.
The Ipsa, which is down more than 14 percent this year, closed at 3,671.78, its lowest since early September.
Mexico's IPC index inched up 0.13 percent to close at 41,002.68 points, helped by a 3.04 percent rise in shares of bank Grupo Financiero Banorte.