Montreal's executive committee member in charge of finance says opposition leader Louise Harel should have known better than to make a personal guarantee on a $240,000 loan to her party during last fall's election campaign.

It is illegal for an elected official to guarantee a loan of more than $10,000.

Harel says she made an honest mistake, and was not aware of the electoral-law limit.

Alan De Sousa said Harel's loan guarantee would put taxpayers in a position of reimbursing Vision Montreal expenses.

"It allowed them to spend monies, and, secondly, apply for reimbursements. Should Montrealers be on the hook to reimburse campaign expenses that were obtained through illegal loans? I think not," said De Sousa.

Harel said she contacted election officials as soon as she learned backing a loan in that amount was illegal.

"No public funds were used and no private illegal contributions were accepted. (There was no) fraudulent attempt against the law," she said.

Harel added that her party is working to "rectify the situation."

Union Montreal pointed out that Harel is a former municipal affairs minister, and suggested that she should be familiar with electoral laws.