President Trump continued to pound home on the message on America’s trade deficit with China on Twitter Saturday afternoon.

While concerns have mounted about a possible “trade war” emerging between the United States and China, since each have slapped tariffs on each others’ imports, the president insisted that the U.S. cannot continue to put up with the unfair trade practices.

Trump tweeted:

The United States hasn’t had a Trade Surplus with China in 40 years. They must end unfair trade, take down barriers and charge only Reciprocal Tariffs. The U.S. is losing $500 Billion a year, and has been losing Billions of Dollars for decades. Cannot continue!