TORONTO (AP) -- A leading Cabinet minister in Canadian Prime Minister Justin Trudeau's government resigned Monday, becoming the second minister to step down over a scandal that has shaken the government in an election year.
Treasury Board president Jane Philpott, considered a star minister, said in a resignation letter that it was "untenable" for her to continue in the Cabinet because she lost confidence and could not defend the government.
Philpott's friend, former Attorney General and Justice Minister Jody Wilson-Raybould, testified last week that Trudeau and senior members of his government inappropriately tried to pressure her to avoid prosecution of a major Canadian engineering company in a case involving allegations of corruption in Libya.
Wilson-Raybould resigned from Cabinet last month after being demoted to veteran affairs minister the month before.
The scandal has rocked Trudeau's government. Gerald Butts, his closet adviser and best friend, also resigned last month and is scheduled to testify Wednesday before a Parliament justice committee in Trudeau's defense.
Trudeau has acknowledged raising the issue with Wilson-Raybould, but has said that was appropriate.
"I have been considering the events that have shaken the federal government in recent weeks and after serious reflection, I have concluded that I must resign as a member of Cabinet," Philpott wrote. "Sadly, I have lost confidence in how the government has dealt with this matter and in how it has responded to the issues raised."
Philpot, a physician, is a former minister of health and minister of indigenous services and was widely viewed as of one of Trudeau's most competent Cabinet ministers.
"Unfortunately, the evidence of efforts by politicians and/or officials to pressure the former Attorney General to intervene in the criminal case involving SNC-Lavalin, and the evidence as to the content of those efforts have raised serious concerns for me," Philpott wrote.
"I must abide by my core values, my ethical responsibilities and constitutional obligations. There can be a cost to acting on one's principles, but there is a bigger cost to abandoning them."
Philpott said she would continue as a Parliament member for Trudeau's Liberal Party.
Wilson-Raybould said the same last week but declined to say she had confidence in Trudeau. Trudeau said earlier Monday he was still deciding whether Wilson-Raybould could remain a member of his party in Parliament.
Trudeau thanked Philpott for her service in a short statement that said he would have more to say later in Toronto.
The leader of the opposition Conservative Party, Andrew Scheer, said at a news conference that Philpott's resignation demonstrates "a government in total chaos" and called again for Trudeau to resign and for a police investigation of the affair.
Wilson-Raybould testified last week she was pressured to instruct the director of public prosecutions to negotiate a remediation agreement with SNC-Lavalin. The agreement would have allowed the company to pay reparations but avoid a criminal trial on charges of corruption and bribery. But Wilson-Raybould said the pressure was not illegal and said she was not instructed to interfere.
If convicted criminally, the Montreal-based company would be banned from receiving any federal government business for a decade. SNC-Lavalin is an economic force in Canada, with 9,000 employees in the country and about 50,000 worldwide.
Celina Caesar-Chavannes, a lawmaker in Trudeau's party that announced last week that she won't seek re-election, tweeted her support for Philpott and thanked her.
"When you add women, please do not expect the status quo. Expect us to make correct decisions, stand for what is right and exit when values are compromised," she tweeted.
Trudeau promoted himself as a feminist when he became prime minister in 2015. Now two of his most high-profile female Cabinet ministers have resigned in solidarity.
"This is a spectacular blow to the government" said Nelson Wiseman, a political science professor at the University of Toronto. "It has become rare that ministers resign on principle in Canada. And now we've had two in such a short time. It reveals deep division in the Cabinet about how to deal with Jody Wilson-Raybould."
He said he thinks that most ministers and Liberal lawmakers want to kick her out of the party and that Philpott does not agree with them.
Wiseman said the last time he can recall something like this was in 1963 when three Cabinet ministers resigned over then Prime Minister John Diefenbaker's opposition to the stationing of American nuclear weapons on Canadian soil.
"This blow won't bring down the government, and Trudeau, like Diefenbaker, will survive and fight back," Wiseman said. "Perhaps, again like Diefenbaker, he will lose the next election but it is too early to be definitive about an election so many months away."
Robert Bothwell, a professor at the University of Toronto, said the resignations speak to Trudeau's failure to connect with his own troops.
"His failure to give a vigorous but reasoned response at the beginning of this pseudo-scandal allowed it to grow into Godzilla," Bothwell said.
Bothwell said Trudeau is not like his father, the late Prime Minister Pierre Trudeau, who swept to office in 1968 on a wave of support dubbed "Trudeaumania" and governed for most of the next two decades.
"Previous prime ministers benefited from experience and seniority, or respect, or fear, or just the feeling that they knew the way better than anybody else. Trudeau the father had all these attributes," Bothwell said.