Bolivia said Thursday it earned $6.06 billion in revenue last year from the sale of natural gas to Argentina and Brazil, where demand was high amid that nation's preparations to host the 2014 World Cup.

Those revenues were up 11.9 percent from 2012, when they came in at $5.4 billion, Bolivian state-owned energy company YPFB said in a statement.

Revenues from natural gas exports are the mainstay of Bolivia's economy.

In December, Bolivia exported an average of 32.16 million cubic meters (1.1 billion cubic feet) of natural gas per day to Brazil.

Brazil's natural gas demand was strong last year due to low water levels in the reservoirs that drive its hydroelectric power plants and the country's preparations for the World Cup, YPFB's natural gas director, Jorge Sosa, said.

Argentina imported an average of 14.55 million cmd (512.8 million cfd) of natural gas in December, while Bolivia's domestic market required some 9.69 million cmd.

Bolivia also exports liquefied petroleum gas in lesser volumes to Peru and Paraguay. EFE