MADRID (Reuters) - Spanish security company Prosegur (>> Prosegur Compania de Seguridad SA) is considering listing about 30 percent of its cash-in-transit unit through an initial public offering in Madrid, Bloomberg reported, citing unnamed sources with knowledge of the matter.

Banks including Goldman Sachs (>> Goldman Sachs Group Inc) and Bank of America (>> Bank of America Corp) are working with Prosegur on the transaction, which could value the stake at 1 billion euros ((711 million pounds), Bloomberg said.

No final decision has been made and Prosegur may still decide against the sale, it said.

Prosegur was not immediately available for comment.

(Reporting by Robert Hetz; Writing by Tracy Rucinski, editing by John Stonestreet)