The arms package includes 114 Patriot missiles, 60 Black Hawk helicopters and communications equipment for Taiwan's F-16 fleet, the agency said in a statement.
Chinese Vice Foreign Minister He Yafei said the proposals would have a "serious negative impact" on co-operation between the US and China.BBC News - US announces Taiwan arms sale plansThe Pentagon has notified Congress of a proposed arms sale to Taiwan, worth $6bn (£3.7bn).
The weapons, including helicopters and anti-missile defences, are part of a package first pledged by the Bush administration.
Beijing considers the self-governed island a breakaway province of China and reacted angrily, saying the move would "seriously damage" its US ties.
Taiwan split from China at the end of the country's civil war in 1949.
Beijing has hundreds of missiles pointed at the island and has threatened in the past to use force to bring it under its control.