The Globe and Mail reports in its Wednesday edition that the American ambassador to Canada delivered an expletive-filled dressing-down to Ontario's representative in Washington during a prestigious event in Ottawa on Monday, according to two sources, who said the tirade focused on an anti-tariff ad commissioned by the province. The Globe's Robert Fife writes that U.S. Ambassador Pete Hoekstra confronted David Paterson, Ontario's representative, at the annual Canadian American Business Council gala at the National Art Gallery. Mr. Hoekstra began to swear at Mr. Paterson over the Ontario ad, which has riled up U.S. President Donald Trump. The President cited the ad as the reason he abruptly cancelled trade talks with Canada last week and later threatened to impose another 10-per-cent tariff on Canadian goods. The ambassador was overheard saying Canada was close to a tariff deal on steel, aluminum and energy, but that Premier Doug Ford had scuttled that goodwill. The Ontario ad featured pro-free-trade remarks by former president Ronald Reagan. It had 11.4 billion impressions over the past week through social media and has been widely covered by news outlets. Mr. Hoekstra hung up when The Globe called his cellphone.