LONDON -- Canada's House of Commons speaker apologized for praising a Ukrainian veteran who fought for a Nazi unit.

During Ukrainian President Volodymyr Zelenskyy's visit to the Canadian parliament on Ov FinanceFriday, speaker Anthony Rota called 98-year-old veteran Yaroslav Hunka a "hero."

Hunka, who was in the crowd and received two standing ovations, served as a member of the 14th Waffen Grenadier Division of the SS before retiring to Canada.

Jewish human rights groups raised concern, with The Friends of Simon Wiesenthal Center calling the praise shocking and outrageous, claiming that Hunka's military unit was implicated in the mass murder of Jews and others.

"There should be no confusion that this unit was responsible for the mass murder of innocent civilians with a level of brutality and malice that is unimaginable," a statement by FSWC reads.

On Sunday, the speaker issued an official apology.

"I have subsequently become aware of more information which causes me to regret my decision," Rota said. "I particularly want to extend my deepest apologies to Jewish communities in Canada and around the world."

He also took on full responsibility for admitting and praising the veteran in the Canadian Parliament, saying that no one among the Ukrainian delegation or the fellow parliamentarians knew about his plans or remarks beforehand.

The opposition however has called for Canadian Prime Minister Justin Trudeau to apologize and investigate. Trudeau's office said that Rota's apology was "the right thing to do" and that he acted alone.

The 14th Waffen-SS Grenadier Division, also known as the Galicia Division, was a voluntary unit made up mostly of ethnic Ukrainians under Nazi command.

Although the unit has not been found guilty of any war crimes by a tribunal, its members are accused of killing Jewish civilians, BBC News reported.