US President Donald Trump hit back at Canada on Sunday after Prime Minister Mark Carney announced retaliatory tariffs on the United States following a breakdown in trade negotiations. "Canada wants the benefits of being a State, without being one!!!" Trump said in a post on Truth Social. "They have also charged our great farmers, for many years, massive amounts of Tariffs. No more!!!" he said. Carney said Saturday that new Canadian tariffs would take effect on September 8, notably targeting the US steel and dairy industries. New 50-percent US tariffs impacting about $20 billion worth of goods, or 5.5 percent of Canadian exports to the US, came into force Saturday. Trump had previously said Washington "should be able to have a deal with Canada," citing his "good relationship" with Carney. But on Saturday, Canada's prime minister said Trump set conditions that were ultimately unacceptable even though earlier talks had been positive. "In recent days, the United States proposed new terms that were uneconomic, unfair and undermined the net benefits for Canada, and called into question the reliability of any deal," Carney said in Ottawa. "We cannot accept what they've offered, and we will not give what they've asked."