The Wildrose party issued an apology Friday on behalf of finance critic Derek Fildebrandt, who was under fire from various parties for ridiculing Ontario Premier Kathleen Wynne during a visit to the Alberta legislature.

Wildrose house leader Nathan Cooper said it was a mistake to insult Wynne while she was a guest at the legislature Thursday.

But the Wildrose stands by comments made by Fildebrandt lambasting Ontario's financial record while suggesting Wynne is leader of a failed, debt-ridden province.

Cooper said Wildrose Leader Brian Jean signed off on the Fildebrandt comments but the party was not expecting Wynne to be in the gallery when they were stated.

"The questions that we asked were fair, but certainly a more appropriate time could have been found, particularly when a visiting dignitary was not in the gallery," Cooper said Friday. "We didn't have a respectful tone yesterday. We express regret for how things unfolded."

Cooper said the Wildrose never wanted to embarrass the premier.  

Out of character for the province

But other Alberta politicians slammed the treatment of Wynne by the Wildrose, suggesting the ridiculing during a guest appearance was out of character for the province. 

"There is just not a level of maturity there that I think Albertans expect to see in their official Opposition," said Brian Mason, house leader for the governing NDP. "If that's how they're going to approach things, we'll become isolated very quickly in this country and won't be able to achieve our objectives, including getting a pipeline to tidewater."

On Thursday, Mason had immediately responded to Fildebrandts comments by saying: "You're so tacky."

Wynne, who sat silently in the legislature gallery as Fildebrandt hurled the insults, was in Edmonton to meet with Alberta Premier Rachel Notley to discuss climate change and other initiatives. 

As she looked on, Fildebrandt demanded to know why Wynne, a Liberal, was invited while right-centrist neighbouring Premier Brad Wall of Saskatchewan was not.

"Invite Premier Wall here! Invite Premier Wall," Fildebrandt shouted at Notley during question period. 

"Currently Ontario has the largest subnational sovereign debt on the planet," Fildebrandt told the assembly. "They're now even receiving equalization payments. It's an example of what happens when a government fails to get its spending under control."

Notley at the time responded by saying the actions demonstrated why the Wildrose "are simply not ready" to govern.

"In the past, when Alberta has actually been able to play a leadership role in the country, they have done so by being grown-ups," she said.

Brian Mason calls Wildrose actions 'rude'1:31

'Shocked and saddened'

On Friday, Alberta Liberal Leader David Swann released a statement saying he was "shocked and saddened" by Wynne's treatment.

"I have spent yesterday afternoon and evening in a state of disbelief at the reception" of Wynne, said Swann in a statement. 

Swann suggested there may be a fair bit of hypocrisy in the Wildrose actions.

"I can only imagine the response of the Wildrose should any Albertan premier receive similar treatment in any of Canada's legislative assemblies," he said.

Greg Clark, leader of the Alberta Party, said on social media that it's "common courtesy to extend a warm welcome to your guests."

Added Clark: "That's what we do in Alberta."

'Childish and petulant'

Even one prominent politician outside of provincial politics weighed in.

Calgary Mayor Naheed Nenshi called Fildebrandt's actions "childish and petulant" and apologized for the way she was treated.

"I was quite shocked to see the so-called shadow finance minister, who has yet to reveal any shadow budget or really any ideas whatsoever about the province, treat a guest in that manner and I did apologize," said Nenshi.

Wynne was in Calgary Friday meeting with the mayor and business leaders.

On Twitter Mason thanked Nenshi for treating Wynne "with some old fashioned Alberta hospitality."

With files from the Canadian Press