Some Liberal MPs are mounting a new effort to oust Justin Trudeau

Pressure is building on the prime minister and his office as a growing number of anxious Liberal MPs are co-ordinating efforts to force Justin Trudeau to step down as Liberal Party leader, multiple sources have told CBC News.

Disgruntled Liberal MPsheld a series of meetings to discuss a path forward for the party since the surprisingToronto-St. Paul's byelection loss in June.

Those talks accelerated withParliament's return and the Montreal byelection loss. Theyescalated further this week with the prime minister and his chief of staff, Katie Telford, out of the country for a summit in Asia.

Some MPs are being asked to sign their names to what amounts to a pledge to stand together in calling for Trudeau to resign, multiple sources said.

The document isn't a letter to be circulated;sources describe it as a vehicle to secure a commitment from MPs toseek a leadership change, and to bind the MPs to that goal if the prime minister and his supporters push back.

WATCH |Some Liberal MPs mount new effort to oust Justin Trudeau:

Some Liberal MPs mount new effort to oust Justin Trudeau

2 days ago

Duration 2:11

CBC News has learned new details about an intensifying effort to push Justin Trudeau out as Liberal leader as some MPs are asked to sign a tightly controlled document, pledging their support for a leadership change.

MPs were pulled into meetings across Parliament Hill this week to sign on to the demand for change at the top.

Multiple sources told CBC News that MPs have been signing a single document that is being tightly controlled no copies or photos of it are being circulated.

All the sources spoke to CBC News on the condition they not be named due to the sensitivity of the internal discussions.

These sources said at least 20 MPs have signed the document so far, with others voicing their support for the cause.

One MP who signed the document told CBC News the number of MP signatures has spilled onto a second page.

That same MP said other caucus members have called since word of the document's existence started to spread, indicating they wanted to sign it.

One Liberal who is part of the effort said the intention was to keep this initiative quiet until they had strength in numbers.

The fear is that moving too early would allow the Prime Minister's Office (PMO) to push back and splinter the calls for change, as they did in the summer in the wake of that bruising Toronto byelection defeat.

That's why MPs are being asked to sign the document now. It's an insurance policy of sorts, signed in ink by the MPsthemselves so that it can't be disavowed if the pressure gets too high.

The Toronto Star first reported this week on meetings to discuss pressuring Trudeau to step down.

Dissatisfaction with Trudeau's leadership flared up at the Liberal national caucus meeting on Wednesday.

Some MPs were upset that Trudeau travelled to Laos for an international summit with some important questions still left unanswered, including who will replace Jeremy Broadhurst as the Liberal election campaign director.

Broadhurst resigned in early September and his successor hasn't been named. That'scausing some frustration in caucus, given that an election could come at any time in this minority Parliament.

Some MPs are also frustrated that clear calls for staffing changes in the PMO have so far been ignored, sources said.

WATCH |At Issue | Poilievre accuses Trudeau of paralyzing Parliament:

At Issue | Poilievre accuses Trudeau of paralyzing parliament

3 days ago

Duration 22:49

A Liberal-Conservative standoff over releasing unredacted documents to the RCMP grinds parliament to a halt for more than a week. Pierre Poilievre is silenced in the House. Plus, the latest from the foreign interference inquiry.

Trudeau was not made available for comment during a refuelling stop in Honolulu en route back from the ASEAN summit. Instead, Trade Minister Mary Ng told reporters she has full confidence in Trudeau as leader.

"I'm disappointed, because Canadians expect us to be focusing on Canadians and doing this work," she said. "I think that the conversations that we have in caucus remain in caucus."

Ng said she learned about the new effort to oust Trudeau by reading the news when the plane landed. She said she believes Trudeau has enough caucus support to continue.

"We have robust conversations at caucus. I love my caucus colleagues. They are dynamic individuals from across the country," she said. "Having the range of perspectives from caucus is very healthy and very good and it helps us be a good government."

Sources said the decisionto participate in this effort tooust Trudeauhas been a difficult one for many of the MPs. Many like Trudeau personally and think he has been a good prime minister.

This group of MPs had hoped the losses in Toronto and Montreal, and the poor polling numbers, would have convinced Trudeau to leave on his own terms.

With no sign of that happening, some MPs say they feel compelled to act now to try and turn around the party's fortunes.

According to sources, Atlantic caucus chair Kody Blois was among those who spoke at the national caucus meeting about the anxiety over Trudeau's leadership.

Blois told MPs the Atlantic caucus had engaged in"a difficult, frank and open conversation" earlier that day.

The regional caucuses meet first thing Wednesday morning before regrouping later for a national caucus with all Liberal MPs.

Two Liberal sources told CBC Newsthe Atlantic caucus asked the PMO representative, who often attends these meetings, to leave so that they could have discussions in private about the future.

They also asked the English-French interpreters to leave as well, to ensure total privacy.

All past efforts toprompt change in the party and within the PMO have so far failed.

The prime minister has said repeatedly he will stay on to lead the Liberals into the next election campaign.

The CBC's Poll Tracker suggests the Liberals are trailing the Conservatives by some 20 percentage points.