Canadian Prime Minister Justin Trudeau on Monday ceded to opposition pressure to expand a public inquiry into election interference to also probe allegations of treason against some lawmakers for secretly working with foreign governments.

Legislators have been pressing Trudeau's Liberal government to name names following the revelations made last week in a heavily redacted national security committee report.

It also claimed that China and India meddled in Canadian party leadership campaigns, including that of Trudeau's main rival, Tory leader Pierre Poilievre.

MPs were expected on Tuesday to pass an opposition motion calling for an independent inquiry that is already looking into foreign interference in Canada's 2019 and 2021 elections to scrutinize possible treason too.

The inquiry led by Justice Marie-Josee Hogue was launched last September.

"I think it's extremely important that we continue to take foreign interference with all the seriousness that it requires," Trudeau said.

The opposition motion is non-binding on the government, but he said his Liberals would vote with opposition parties to ask Hogue to further investigate the claims so that "Canadians can have confidence in the integrity of their democracy."

In the House of Commons earlier, opposition parties urged transparency.

"Conservatives are demanding that the government expand the scope of the foreign interference public inquiry to receive all documents and information and reveal the names of which MPs have sold out their country," said Tory MP Andrew Scheer.

Bloc Quebecois MP Pierre Paul-Hus, who presented the motion, said: "We need to know who these members are who are collaborating with hostile foreign countries."

He was echoed by New Democratic Party leader and Trudeau ally Jagmeet Singh, who called the findings "deeply troubling" and demanded accountability. "Canadians ought to know," he said.

The National Security and Intelligence Committee of Parliamentarians (NSICOP) in a report last week cited "troubling intelligence that some Parliamentarians are 'semi-witting or witting' participants in the efforts of foreign states to interfere in our politics."

This included the secret funding of political campaigns, sharing of confidential information or privileged information on the work or opinions of fellow lawmakers with foreign intelligence officers, and influencing Canadian lawmakers to advantage a foreign state.

The report did not identify Canadians implicated in the schemes, but chided Ottawa for its "slow response to a known threat."

Public Safety Minister Dominic LeBlanc refused to reveal the identities of lawmakers mentioned in the report, saying doing so was itself illegal.

He also said the allegations in the NSICOP report may include uncorroborated or unverified intelligence information.