Several human rights groups have issued an open letter to Prime Minister Justin Trudeau, asking him to cancel the $15-billion arms deal with Saudi Arabia.

“To provide such a large supply of lethal weapons to a regime with such an appalling record of human rights abuses is immoral and unethical,” says the letter signed by representatives of Amnesty International Canada, Canadians for Justice and Peace in the Middle East, and other agencies.

“The government has had every opportunity to uphold this position, but has chosen not to. We therefore ask the government to rescind the export permits, ensuring that this deal does not go ahead unless and until relevant human rights concerns have been resolved.”

The deal, made by the previous Conservative government, gave Canadian company General Dynamics Land Systems a 15-year contract to manufacture light-armoured military vehicles for Saudi Arabia.

The new Liberal government proceeded with the contract, calling it a done deal that could not be cancelled. But earlier this month, Foreign Affairs Minister Stephane Dion came under fire for quietly approving the export of the bulk of the LAV3s to the desert kingdom. Critics said Dion’s final approval shows the contract was not a done deal and could have been avoided.

Dion has said that there is no evidence that Saudi forces will use Canadian-made LAVs against its own people.

But Alex Neve, the secretary general of Amnesty International Canada, told a news conference in Ottawa Wednesday that “mounting information” about Saudi forces’ human rights violations suggests otherwise.

“The likelihood that these light armoured vehicles will end up implicated in that is very serious,” Neve said.

Trudeau has defended his government’s decision to sign the export permits, saying that the issue is a “matter of principle,” and Canada must respect its contracts.

But the open letter to the prime minister says the Saudi contract “is precisely the type of deal that Canada’s export controls are intended to prevent.

“The Government of Canada must enforce our existing export control policy and regulations, which should prohibit arms sales to governments that have a ‘persistent record of serious violations of the human rights of their citizens,’ and that are ‘involved in or under imminent threat of hostilities,’” the letter says.

The contract is expected to create about 3,000 jobs in Ontario.