US President Donald Trump called Chinese trade practices “vicious” on Wednesday, his latest blast at the world’s second-biggest economy as the two sides slug it out in a deepening trade war.

“China is targeting our farmers, who they know I love & respect, as a way of getting me to continue allowing them to take advantage of the U.S.,” Trump said on Twitter, while his protectionist trade policies face increasing criticism from within his own Republican Party.

“They are being vicious in what will be their failed attempt. We were being nice – until now! China made $517 Billion on us last year.”