Veteran NDP MP Charlie Angus is suggesting his former leader needs to work through hard feelings about being rejected by the party almost three years ago.
Angus took to Twitter Sunday to share some thoughts about Tom Mulcair, someone he worked with for years.
HuffPost Canada reached out to Angus to ask what precipitated the tweet, which came on the heels of another unpleasant headline for the party because of Mulcair's punditry.
Mulcair has lots of thoughts about the NDP these days
The ex-NDP leader, who in August officially resigned his seat in the Quebec riding of Outremont to teach at the Université de Montréal, regularly provides political commentary for CTV News. Mulcair's appearances on CTV's "Question Period" have not always been kind to his successor, Jagmeet Singh, who is currently fighting to win a byelection in the B.C. riding of Burnaby South.
In recent weeks, Mulcair has suggested Singh won't be able to stay on as leader if he loses his byelection and criticized the current NDP leader's response to a question on China. He has also said "several" current NDP MPs have told him they won't run again this fall.
Many party stalwarts have already announced they won't re-offer this year including Romeo Saganash, David Christopherson, and Irene Mathyssen.
In an episode that aired Sunday, Mulcair suggested progressive voters may find themselves voting for the Green Party in October.
More from HuffPost Canada:
Mulcair made the remark in a segment with political journalists that also touched on the Liberal government's measures to prevent election meddling from foreign actors and the politically charged trial of Vice-Admiral Mark Norman.
Host Evan Solomon noted that Green Party Leader Elizabeth May was on the show earlier, basking in the glory of some record fundraising numbers for the party. According to financial returns filed with Elections Canada, the Greens raised $1.5 million in the fourth quarter last year and $3.1 million for the year.
The NDP, meanwhile, raked in $1.97 million over the last three months of 2018 and just under $5.2 million for the year.
"They're literally nipping at the heels of the NDP. What do you make of that?" Solomon asked Mulcair.
"I wasn't surprised by those numbers, in fact I've been predicting it for a while, Evan, for one good and simple reason: progressives are looking for a home on environmental issues," Mulcair responded.
'Mr. Singh has now decided that he's going to support a liquified natural gas pipeline'
Mulcair noted the Liberal purchase of the Trans Mountain pipeline expansion project, but also highlighted that "Mr. Singh has now decided that he's going to support a liquified natural gas pipeline."
Mulcair was referring to the $40-billion liquified natural gas project in northern B.C. that has the backing of Singh and the B.C. NDP government of John Horgan.
The ex-NDP leader said Canadians could send enough of a "contingent" of Green MPs to Ottawa after the next election to press whichever party forms government on environmental issues.
Watch the full segment:
Days earlier, Mulcair was also asked by CTV if New Democrats are getting more vocal that Singh can't stay on as leader if he loses his byelection bid. CBC News reported last month that "several" senior members of the caucus told Singh in June that a loss in Burnaby South would spell the end of his leadership.
Mulcair said that New Democrats have not typically aired "dirty laundry" in public and that the change is a "reflection of how dire things are in the minds of those people."
Mulcair's commentary about the challenges New Democrats are facing has not always been appreciated by party members.
Ian Capstick, a former NDP press secretary before Mulcair became leader, claimed last month that Mulcair "attempts revenge" when he doesn't get his way.
"It's not helpful, and I think it's inappropriate frankly that, as leader, he should be making comments, issuing commentary on the current leader," Robinson told the paper.
Though polls suggested at the start of the 2015 election that Mulcair had a shot at becoming Canada's first NDP prime minister, the party ended up capturing only 44 seats. At the NDP convention in April 2016, 52 per cent of delegates voted in favour of calling a leadership race to replace him.
Still, Mulcair opted to stay on as leader in an interim capacity until his replacement was chosen in 2017.
Angus finished a distant second in that leadership contest, which was won on the first ballot by Singh.
Angus was accused of taking his own swipe at Singh in early 2018 with a tweet after the NDP leader's very public proposal to his now wife.
"When a party believes that better Instagram tricks or gala planning is the path to success we lose touch," Angus wrote at the time.
He later deleted the post and told reporters it wasn't helpful.
With files from The Canadian Press