The RCMP says Joe Fontana was charged Wednesday with fraud under $5,000, breach of trust by a public official and uttering forged documents.
The force says the charges followed an investigation that began after it was contacted by the House of Commons last month regarding the allegations.
No details were provided about those allegations, but the London Free Press has reported two government of Canada cheques were given to a London club to cover the cost of the wedding reception for Fontana's son Michael in 2005.
It said the first cheque was for a deposit of $1,700 and a second cheque for $18,900 was received several months later.
A media officer with the RCMP says the value of fraud Fontana is charged with is set at $1,700.
"At this time, there is no evidence to suggest or support that other government funding was received for Joseph Fontana's personal expenses," said RCMP Sgt. Richard Rollings.
Fontana has previously denied the allegations.
In a letter posted on his website on Tuesday, he did not directly address the allegations but said he would not let them interfere with his job as mayor.
"Make no mistake, I treat the allegations that have been levied as serious, but I have not and will not allow them to be a distraction from my duties and obligations of my office,'' Fontana wrote.
"I will not stand aside or leave my responsibilities as mayor," wrote Fontana.
A motion was to be tabled at the city's finance committee on Monday calling on Fontana to temporarily step aside as mayor pending the outcome of the RCMP investigation.
A similar motion was introduced at council on Oct. 30 but was shut down without debate.
"This is very disconcerting," said Coun. Joni Baechler.
"I think it lends credence to my request, which was going to be on Monday (at finance committee), that he step aside until the allegations are dealt with in court."
Fontana's lawyer, Gordon Cudmore, says the mayor will appear at a news conference Thursday to address his "political future."
Cudmore refused to say whether Fontana would announce plans to temporarily step aside as mayor.
Fontana is to appear in court on Jan. 8.
(AM980, The Canadian Press)
Note to readers: This is a corrected story. An earlier version included an incorrect first name for Joe Fontana's son.
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