Ambrose, who was in Montreal to meet with female business leaders, said the prime minister "did the job he should do" during his trip to the United States in order to "make connections" with President Barack Obama.
She said she was disappointed, however, that Trudeau didn't take Natural Resources Minister Jim Carr with him to Washington or press the president on energy issues affecting both countries.
Interim Conservative party leader Rona Ambrose speaks to reporters as Quebec lieutenant Denis Lebel looks on at a news conference, Monday, March 14, 2016 in Montreal. (Photo: Ryan Remiorz/CP)
"Yes there was a big party and it was very nice and there was a lot of people who enjoyed it," she said referring to last week's high-profile, celebrity-filled state dinner with the Obamas.
"But there wasn't anything concrete that came out of (the visit). We'll wait and see and hope there will be opportunity for Mr. Trudeau to use the relationship he has with Obama to press for opportunities for Canadians. Canadians need to get benefits from this relationship."
Ambrose said the energy industry played too minor a role in discussions between the two leaders and Trudeau should have pushed Obama to revisit his decision to reject the Keystone XL pipeline.
Top Tory blasts Grits' deficit plan
She also criticized the government for its reported plan to run larger annual deficits than the $10-billion cap Trudeau promised during the fall election campaign.
Ambrose said when the government tables its budget March 22, the deficit could top $30 billion.
"All that borrowed money is going to have to be paid back," she said, adding the government will have to either raises taxes or make cuts to bring spending under control in the coming years.
The Trudeau government says budget deficits will help spur growth and bring in additional government revenues.
"We will be pushing the federal government to live within its means," Ambrose said.
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