The comments come as the Liberal government is facing new pressure to cancel the deal amid international outrage over the killing of Saudi journalist Jamal Khashoggi earlier this month.
Canada has added its voice to global calls for answers, with Trudeau saying on Tuesday that the Saudi government’s explanation of what happened lacks credibility.
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“That’s why we are pushing for real clear answers on this,” he said in a Tuesday interview with the CBC.
“It is unacceptable and unthinkable that someone could have murdered a journalist on foreign soil like this. That is something that the global community cannot stand for and we’re being very clear about that.”
Human rights groups have urged Canada to cancel the $15-billion contract to sell light armoured vehicles to Saudi Arabia – a 2014 deal signed by the Harper government and upheld by the Liberals.
But while saying the government could suspend export permits, Trudeau said the “difficult” contract is structured in a way that “makes it very difficult to suspend or leave the contract.”
“I do not want to leave Canadians holding a billion-dollar bill because we’re trying to move forward on doing the right thing,” he added. “So we’re navigating this very carefully.”
In a separate interview on 1310 News in Ottawa, Trudeau said he did not want Canadians “forking over billions of dollars to Saudi Arabia because we’re standing up for human rights.”
On Monday, Foreign Minister Chrystia Freeland said Canada is “gravely concerned by the murder” of Khashoggi, adding there are “very important questions” about the entire relationship with Saudi Arabia.
Human-rights groups have long opposed the deal over a lack of transparency and fears the Saudi government has used the Canadian-made vehicles to commit atrocities against its own people.
The vehicles are being built by General Dynamics Land Systems in London, Ont.
The Saudi deal has been billed as the largest arms-export contract in Canadian history.