SAO PAULO (Reuters) -Brazilian beef-packers' lobby Abiec, which represents companies including JBS and Marfrig, on Tuesday estimated losses of $1 billion if the United States applies a 50% tariff on Brazilian exports.

The U.S. is Brazil's second biggest beef export destination after China.

Roberto Perosa, head of Abiec, said Brazilian beef companies had expected to sell some 400,000 tons by yearend to the U.S., but imposition of a 50% tariff would make sales "inviable." No market can immediately replace the U.S. based on the sheer volume demanded by the importers and the price they are in a position to pay, he said.

Brazilian beef-packers exported around 181,000 metric tons of beef worth $1 billion to the U.S. in the first half of this year, according to trade data, equivalent to around 12% of the country's total beef exports.

The trade represented a nearly 113% increase by volume and a 102% increase by revenue on an annual basis, reflecting strong demand for the Brazilian product, which is mainly processed to make hamburgers for the United States.

Speaking at a live event, Perosa said sector representatives are having talks with lawmakers in the U.S. hoping they can help avert enforcement of the new tariffs from August 1.

He said a lack of Brazilian exports would spur domestic beef inflation in the U.S., which has been grappling with scarce cattle supplies and has been increasingly relying on beef imports.