Canadian Prime Minister Justin Trudeau said Thursday that he failed to realize an "erosion of trust" between himself and former attorney general Jody Wilson-Raybould on the SNC-Lavalin case, though he acknowledged he could have acted differently.

"I was not aware of that erosion of trust ... I should have been," Trudeau told a press conference in the morning at Ottawa's National Press Theater on the political crisis that has triggered the resignation of two female ministers as well as his principal secretary Gerald Butts.

Butts testified on Wednesday before the Justice Committee of House of Commons, blaming the crisis engulfing the Liberal government on a breakdown in trust and communications.

Trudeau offered no apologies for what has taken place, acknowledged no wrongdoing in what has unfolded since the Canadian newspaper The Globe and Mail reported on Feb. 7 that senior officials of his government tried to pressure Wilson-Raybould into dropping a criminal prosecution of Montreal-based engineering and construction services giant SNC-Lavalin.

Trudeau has denied the allegations, saying that he and his staff acted properly, and in the interest of thousands of jobs.

Wilson-Raybould, who resigned from the cabinet last month, testified before the Justice Committee that she faced "consistent and sustained" political pressure and "veiled threats" from Trudeau and 11 senior officials, to offer a deferred prosecution agreement to SNC-Lavalin.

SNC-Lavalin was facing bribery and corruption charges over business dealings in Libya.

Trudeau denied the accusations, saying he disagreed with her characterization of events. Butts resigned two weeks after her testimony and he appeared before the same committee Wednesday to offer his side of the story.

Butts denied being a part of, or being aware of, any interactions with Wilson-Raybould that could constitute pressure. He said that she never raised with him that she felt any of the conduct on the case was improper.

Nevertheless, Butts confirmed a breakdown in trust between Trudeau and Wilson-Raybould, saying her being shuffled out of the justice minister role as the flashpoint for the ongoing case.

Wilson-Raybould served minister of justice and attorney general from 2015 until January 2019 -- the two titles are traditionally held by the same cabinet member -- and then as minister of veterans affairs before resigning from Trudeau's cabinet in February.

Trudeau acknowledged that he should have paid more attention to growing friction between his staff and Wilson-Raybould.

"What has become clear over the various testimonies is over the past months there was an erosion of trust between my office, my former principal secretary and the former attorney-general," Trudeau said.

The prime minister said that in hindsight, he should have reached out personally to Wilson-Raybould on the matter.

Asked whether he was making an apology, Trudeau indicated he was not. He said he won't apologize for defending SNC-Lavalin jobs. He characterized what has happened as a case where "situations were experienced differently -- and I regret that."

Trudeau said he has asked for a set of external set of opinions on the dual role of the justice minister and attorney general, as well as the operating policies for cabinet ministers and staff related to dealings on judicial matters.

The prime minister said he will be seeking outside advice on whether to separate the posts of attorney-general and justice minister as well as practices and operations of cabinet.

However, the opposition parties urged further probes. Conservative Party Leader Andrew Scheer has repeatedly urged an investigation and called for Trudeau to resign as he "lost the moral authority to govern."