U.S. Trade Representative Jamieson Greer on Monday said Canada was responsible for the collapse of trade-deal negotiations last week, telling CNBC that Ottawa changed its demands at the eleventh hour.

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“We progressed to a point Tuesday night where we had enough agreement among the parties to announce that we had we had found the way to a deal,” Greer told CNBC’s “Squawk Box.”

“Then we set about to finalize it, and then in the last hours, I think there were things that the Canadians just — you know, they wanted more,” he said.

The comments mirror those offered by Canadian Prime Minister Mark Carney, who had accused the U.S. of proposing “last-minute changes” that were “unfair, uneconomic, and called into question the reliability of any deal.”

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Greer spoke to CNBC three days after Canadian negotiators left Washington without a deal to prevent President Donald Trump from enacting new 50% tariffs on about $20 billion worth of goods, including imports of wine, hockey sticks, cement and other goods.

Those duties took effect at 12:01 a.m. ET on Saturday, stoking alarm from business groups in the U.S. and Canada alike who warn that they could raise costs and wreak havoc on exposed industries.

Carney said Canada will retaliate with “dollar for dollar” tariffs against the U.S.

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