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U.S. Ambassador Kirsten Hillman and Intergovernmental Affairs Minister Dominic LeBlanc in Washington in May. The two officials met with U.S. representatives again this week as Canada pushes for a trade deal with President Donald Trump’s administration.Adrian Wyld/The Canadian Press

Dominic LeBlanc is warning that negotiators “have a lot of work in front of us” before concluding a trade deal with the U.S., after Prime Minister Mark Carney signalled that the talks may miss an Aug. 1 deadline.

Mr. LeBlanc, who met with U.S. Commerce Secretary Howard Lutnick and five Republican Senators over the course of a two-day visit to Washington, said talks with Mr. Lutnick were “productive” and “cordial,” but he was circumspect on the prospects for a deal.

“Canadians expect us to take the time necessary to get the best deal we can in the interest of Canadian workers. So we’re only going to be in a position to accept the deal when the Prime Minister decides that it’s the best deal we can get,” the Intergovernmental Affairs Minister told reporters on Capitol Hill Thursday.

“All of these deadlines are with the understanding that we’ll take the time necessary to get the best deal.”

Kirsten Hillman, Canada’s ambassador to the U.S., added: “There is a time when the deal is the right deal, and it’s important for us to be in a position to continue negotiating until we get to that point.”

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Mr. LeBlanc said he met with Mr. Lutnick for 90 minutes on Wednesday night and planned to be back in Washington next week.

Mr. LeBlanc said his discussions with the Commerce Secretary were about how to “return to the circumstances that existed before the last few months” in the economic relationship between the two countries.

The Intergovernmental Affairs Minister and the Ambassador also sat down with Republican Senators Kevin Cramer of North Dakota, Roger Marshall of Kansas, Shelley Moore Capito of West Virginia, Todd Young of Indiana, and Tim Scott of North Carolina.

U.S. President Donald Trump and Mr. Carney agreed at the G7 summit in Kananaskis, Alta., in June to reach an economic and security deal within a month. That deadline was later revised to July 21. Then, after Mr. Trump threatened more tariffs on Canada and a long list of other countries around the world, he set Aug. 1 as the new deadline.

But Mr. Carney earlier this week suggested that he wasn’t bound by such a date if he couldn’t reach an agreement to his liking.

He told reporters that Canada “will not accept a bad deal” just to be finished by Aug. 1.

“Our objective is not to reach a deal whatever it costs. We are pursuing a deal that will be in the interest of Canadians.”

Mr. Carney has also signalled that Canada may have to accept that some of Mr. Trump’s tariffs are here to stay as part of a deal, in contrast with Canada’s earlier negotiating position that all of the tariffs had to go.

Prime Minister Mark Carney played down the importance of a looming Aug. 1 deadline in trade talks with the U.S. on Tuesday, saying the objective is to get the best possible deal for Canadians.

The Canadian Press

Senator Lisa Murkowski, an Alaska Republican, also expressed pessimism on Thursday that a deal was close. She met with Mr. Carney earlier in the week in Ottawa.

“I wish that I could say it feels good, that this is all going to be taken care of before the 1st of August, but I’m not sensing that,” she said on Capitol Hill.

Canada has many allies among free trade-loving Republicans in the U.S. Congress but Mr. Trump and Mr. Lutnick so far have signalled that they want the U.S. to entirely stop importing cars, steel, aluminum and other goods from Canada.

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The Carney government has met U.S. demands on increased military and border spending and ending a digital services tax, but has so far not appeared to have received any concessions in exchange at the bargaining table.

Mr. LeBlanc said on Thursday that his strategy was to position Canada as being helpful to Mr. Trump’s agenda of toughening borders and taking on China by stopping Beijing from dumping steel into the international market.

“My conversations have focused on how we share so many priorities of President Trump’s administration,” he said.