The Liberal government is facing increasing pressure to make public the most important deliberations on Canada's $15-billion sale of combat vehicles to Saudi Arabia: precisely how the transaction is justified under this country's strict weapons export control regime.

Ottawa has so far declined to spell out how the biggest military sale it has ever brokered passes muster under Canadian export control rules that place restrictions on shipments to countries with a "persistent record of serious violations of the human rights of their citizens." The government cites commercial confidentiality.

Former Conservative cabinet minister Tony Clement called on the Liberals Monday to release or pledge to make public any details of the assessment Ottawa has, or will conduct, on the implications of the shipment for human rights in Saudi Arabia.

Story continues below advertisement

"Canadians don't want these weaponized vehicles to be used against innocents in Saudi Arabia," said Mr. Clement, now foreign-affairs critic for the Conservatives in opposition. "We need to know, given this rapidly changing environment in the Middle East, that the weapons are going to be used for the purposes that are intended and that there has been sufficiently rigorous assessment of Saudi Arabia."

Canada is selling weaponized armoured fighting vehicles to the Saudi Arabian National Guard in a contract first announced in 2014 when the Conservatives were in office. The federal government lobbied for the sale, arranged the transaction and remains the prime contractor for the deal, which will keep about 3,000 workers employed for nearly 15 years. General Dynamics Land Systems, the manufacturer in London, Ont., is still gathering parts and material to make the vehicles.

The Liberals have already pledged to make available a redacted version of an internal 2015 report on the state of human rights in Saudi Arabia, one that will be stripped of sensitive information and advice. Mr. Clement calls that "not even a half measure."

Federal export rules say Ottawa must assure itself that Saudis will not turn these light armoured vehicles (LAVs) against their own people. The export-control regime stipulates that shipments cannot proceed "unless it can be demonstrated there is no reasonable risk that the goods might be used against the civilian population."

Mr. Clement acknowledges that the Conservatives are asking for information they refused to release while in office under Prime Minister Stephen Harper.

But he says the new leadership of the Conservative Party feels differently.

"This is a [Liberal] government that has promised more transparency. I think that is consistent with the times in which we live," Mr. Clement said.

Story continues below advertisement

"So don't take the signal from the last government. If you want to be true to your principles and values, which the Conservative Party under new leadership shares, let's move forward."

New Democratic Party caucus spokeswoman Véronique Breton said the NDP is urging the release of this assessment, as well. "We have great concerns about human rights in this country and we haven't had many clear answers from the government."

Asked last week for the deliberations on how the Saudi arms deal passes the export control test, the Global Affairs department said it can't comment on the export permits or the approval process. It did not immediately reply when asked again Monday. Foreign Affairs Minister Stéphane Dion said last week that the Liberals would revisit the process by which future contracts are assessed but would not block this contract.

At least one member of Mr. Trudeau's cabinet has previously voiced support for the release of this information. More than 10 months ago, before being elected to Parliament, Catherine McKenna, who is now Environment Minister, wrote on Twitter that the "Harper government needs to explain why it is confident Saudi government won't use Canadian armoured vehicles to violate human rights."

It's not clear how much assessment the federal government has already done to determine whether these weaponized fighting vehicles might be used by the Saudis against their own population.

As The Globe and Mail reported last year, Ottawa gave General Dynamics early assurances over whether the arms could be exported, telling the manufacturer in late 2013 or early 2014 that it could find no "red flags" regarding the deal. The Department of Foreign Affairs, since renamed Global Affairs, was careful to leave itself a margin of manoeuvre in this informal review of the transaction, with one bureaucrat saying in a Feb. 12, 2014 e-mail that at no time did the department guarantee to General Dynamics that the sale was officially approved.

Story continues below advertisement

The export will also be reviewed when General Dynamics applies for permits to ship the vehicles to Saudi Arabia. The government refuses to offer any insight into when this will take place, again citing commercial confidentiality.

Activists allege Saudi Arabia sent Canadian-made fighting vehicles into Bahrain in 2011 to help quell a democratic uprising. The Canadian government does not deny this happened. It says only that it does not believe the vehicles were used to beat back protests.