Jane Philpott, who resigned from Prime Minister Justin Trudeau's cabinet earlier this month over the SNC-Lavalin affair, faced a barrage of tough questions from her Liberal colleagues Wednesday during a closed-door session of the Ontario caucus, sources told CBC News.

Philpott addressed the group at the beginning of the meeting, which lasted 30 minutes longer than scheduled and was described by people in the room as "rough" and "uncomfortable."

Philpott — widely considered to be one of the most competent and respected ministers in the Trudeau government — resigned from the Liberal cabinet March 4, saying in a public statement that she had lost confidence in how the Trudeau government was handling the SNC-Lavalin affair.

Today's meeting of the Ontario regional caucus was the first since Philpott resigned. She did not attend today's meeting of the national Liberal caucus.

She remains a member of the caucus and has said she intends to seek re-election as the Liberal candidate in her Markham-Stouffville riding.

Today, some of her fellow Liberal MPs reminded her that others in the caucus had made compromises on sensitive issues such as medical assistance in dying — one of the key pieces of legislation Philpott fronted as health minister, along with then-justice minister Jody Wilson-Raybould.

Wilson-Raybould resigned from cabinet Feb. 12, just days after the Globe and Mail reported that she had been inappropriately pressured by PMO and other officials to overturn a decision by the Director of Public Prosecution Service of Canada to proceed with a criminal prosecution against SNC-Lavalin related to bribery charges for contracts in Libya.

The Montreal-based global engineering and construction company had been seeking a Deferred Prosecution Agreement that would allow it to avoid criminal proceedings and a possible 10-year ban on bidding for federal contracts in the event of a conviction.

Wilson-Raybould also remains in the Liberal caucus and says she will run in the fall campaign under the party's banner.

Trudeau touts 'strong team'

As caucus tensions played out behind closed doors today, Trudeau insisted the Liberals are a "strong team" bound by a collective focus on growing the economy for the middle class, reconciliation with Indigenous peoples and promoting gender equality.

"As the two members in question have indicated, they intend to run as Liberals in the next election," he said during an event in Orleans, Ont., where he was promoting the housing affordability measures in Tuesday's budget. "We will continue to work together and make sure that we're delivering tangibly for Canadians the way we did with this most recent budget."

In the statement announcing her resignation from cabinet, Philpott said that after "serious reflection" on the events that have shaken the federal government in recent weeks, she concluded she must quit.

"I must abide by my core values, my ethical responsibilities and constitutional obligations," she said.

"There can be a cost to acting on one's principles, but there is a bigger cost to abandoning them."

Earlier today, Celina Caesar-Chavannes quit the Liberal caucus, apologizing for harm she had caused through an interview with the Globe and Mail.

The Whitby, Ont. MP told the newspaper that when she first told Trudeau she did not plan to seek re-election, he became hostile towards her.

"He was yelling. He was yelling that I didn't appreciate him, that he'd given me so much," Caesar-Chavannes told the Globe.

The Prime Minister's Office insisted that Trudeau displayed "absolutely no hostility" in the exchange.