Two English-language bands have been told they're being dropped from a St-Jean-Baptiste Day concert in Montreal after one of the sponsors threatened to pull out over language issues.

The sponsor, l'Association culturelle Louis-Hebert, said it did so over concerns the crowd at the six-hour concert would turn violent if English bands were allowed to play.

"There have been some rumours of a demonstration and we didn't want to compromise the festive and familial character of the event," l'Association culturelle Louis-Hebert spokesman Julien Larocque-Dupont told The Canadian Press Monday.

The concert, called "L'Autre St-Jean," is supposed to be an indie alternative to the huge, official Fete nationale du Quebec concert which often features French-Canadian superstars.

Societe Saint-Jean-Baptiste president Mario Beaulieu partnered with the Louis-Hebert Cultural Association to contract the C4 production company to produce the show.

Beaulieu contends that C4 snuck the English-speaking acts in at the last minute without prior approval in order to win publicity.

He claims many francophones saw that as a provocation and his group received a number of complaints.

"The official language of Quebec is French," said Beaulieu. "It's normal that the national holiday should be mainly in French."

He says while English musicians often perform at Fete nationale festivities, they sing in French.

"In the big show, sometimes there are anglophones who come to sing. Many of them happily sing in French and sing a little bit in English and it never causes problems," he told CTV Montreal.

But if the anglo bands are blocked from performing, then the show is finished, said C4 Productions' Pierre Thibault.

"For us, it's all or nothing: no English bands, no show."

C4 Productions says it will make a final decision on Wednesday.

The two English bands involved -- acoustic string band Lake of Stew and hillbilly rock n' roller Bloodshot Bill -- both say they want to play, regardless of the controversy.

The three brothers who make up Lake of Stew say they had been looking forward to the show and were blindsided by the news.

"Here we are thinking, 'Wow, the consciousness and the attitude of the Quebecois people is finally becoming more inclusive.' And then this," band member Richard Rigby told CTV Montreal.

Brother Mike Rigby said he takes great pride in Quebec, even though he is not francophone. "I love the place. It's my home, it's where I grew up," he said.

The change in plans has angered many in the province, some of whom have signed an online petition, promoted on Facebook.

The petition denounces the decision and calls for a "modern Quebec where everyone can proudly declare themselves Quebecers."

Quebec's Culture Minister Christine St-Pierre said the disagreement sends the wrong message to the rest of Canada.

"This is the celebration of all Quebecers," she said.

"People in Quebec want to be inclusive, they don't want to send the message to outside Quebec that we are not."