A melee this week in the House of Commons - where it's normally heckles, not elbows, flying around - is a sign of the "escalating aggressions" between the government and opposition parties, says Green Party Leader Elizabeth May.

She told CTV's Question Period Sunday she's hopeful the government's withdrawal of a motion that would have turned the legislative agenda over to cabinet "could restore decorum and cooperation in the House."

The motion would have let the Liberals force overnight debates and shut down the House for the summer without any notice and with no debate. It would also restrict the opposition parties' ability to slow down proceedings.

May said normal parliamentary decorum was already out the window Wednesday by the time Prime Minister Justin Trudeau rose from his seat, strode across the House floor, and grabbed hold of Conservative whip Gord Brown's arm to escort him to the front of the chamber in an effort to trigger a vote on the Liberals' contentious medically assisted dying bill.

Trudeau elbowed NDP MP Ruth Ellen Brosseau in the process. That triggered a standoff and shouting match between NDP Leader Thomas Mulcair and Trudeau.

The prime minister's conduct is being examined by parliament's procedure and affairs committee. He apologized twice in the House afterward.

The apology was "sincere and heartfelt," Government House Leader Dominic LeBlanc told Question Period, and all legislators should now move on and "get the House of Commons to a better place."

"Canadians elected us to set a new tone and this week was not a good chapter in that effort, but we can do better and we will do better."

Conservative House Leader Andrew Scheer said Trudeau's actions are "unprecedented."

"I've never seen anything like it, to see a prime minister just snap like that and march into a crowd of MPs," he said.

"There is no context in which it's acceptable for the prime minister of this country to leave his seat, charge over to a group of MPs and start throwing his elbows around."

NDP House Leader Peter Julian said Trudeau could have simply instructed his own party's whip to sit, which would have automatically triggered the vote on the motion.

Both house leaders also appeared on CTV's Question Period Sunday.

Julian said it took a joint effort by the Opposition parties and strong public reaction to get Liberals "to back off the most Draconian motion for parliamentary procedure we've ever seen in Canadian history."

The controversial motion was only put forward because it became clear there would be no agreement among the parties about bringing the medically assisted dying bill to a vote, said LeBlanc. He said it will likely come before the House for a vote May 30.

The government's push to pass the bill ahead of a June 6 deadline imposed by a Supreme Court ruling is responsible for current high tensions in the House, said May.

But she blamed the Conservatives for an overall decline in decorum.

"The Conservatives in Opposition, show so little respect to the prime minister. You know I disagreed with Stephen Harper on policy, on almost everything, but I respect the office of prime minister. I think it's appropriate that when the prime minister is answering questions in Question Period he not be loudly heckled. Stephen Harper was never heckled in the way Justin Trudeau is heckled every day."