OTTAWA -- Outgoing Conservative Leader Andrew Scheer placed the blame for the Iran plane crash on "the Iranian Regime alone" in a series of tweets Tuesday 鈥� just one day after Prime Minister Justin Trudeau said the shootdown was due to a recent "escalation" of tensions in the Middle East.

He said his party wants to see Canada take action against Iran, including imposing new sanctions on Iran and listing their Islamic Revolutionary Guard Corps as a terrorist organization.

Scheer also called on Iran to compensate all victims of the crash, repatriate the victims' remains and hold the perpetrators accountable.

"Immediate action is necessary. The Iranian Regime can not get a free pass after killing 57 Canadians," Scheer said in a on Monday.

On Monday night, Trudeau told Global News that the 57 Canadians killed in the crash would still be alive if there hadn't been a ramp-up of tensions in the region recently.

"If there were no tensions, if there was no escalation recently in the region, those Canadians would be right now home with their families," he said.

Tensions between Iran and the United States first heated up when, in 2018, U.S. President Donald Trump withdrew from the 2015 Iran nuclear deal and imposed crippling sanctions on Iran. The tensions exploded on Jan. 3, when a targeted U.S. airstrike in Baghdad, Iraq killed Iranian Gen. Qassem Soleimani.

Shortly afterwards, Iran fired ballistic missiles on two bases in Iraq where American soldiers were stationed. The strikes, according to Iran's Supreme Leader Ayatollah Ali Khamenei, were in retaliation for the U.S. airstrike in Baghdad, Iraq that killed Soleimani.

That tense environment was the reason a civilian aircraft was shot down from the sky, according to Trudeau.

However, Scheer laid blame elsewhere.

"The blame for this horrible atrocity lies with the Iranian Regime alone," Scheer tweeted Tuesday.

Trudeau briefed Scheer on the situation, according to the outgoing Conservative leader. In his series of tweets, Scheer called his demands "measured and appropriate."

"Canada's Conservatives will continue to advocate for an appropriate and measured response to ensure Iran is held accountable and the families of the victims receive the justice they deserve," he said.

Iran is currently leading the investigation of the accident. Canada has two Transportation Safety Board investigators in the region and plans to send two more to analyze the black boxes from the accident, which are damaged, once the details of when and where that analysis will take place are provided.

Trudeau also spoke with Ukrainian President Volodymyr Zelensky on Tuesday. According to a readout of the conversation, the two underscored the need for a "full, complete and credible investigation."

Canada is convening a meeting of International Coordination and Response Group in London, U.K. Jan. 16.