Former President Bill Clinton’s charity work, relationships with world leaders, and business contacts sometimes profitably overlap, raising questions that may affect his wife’s presidential bid, reports The Wall Street Journal.

The newspaper says that Frank Giustra, a Canadian entrepreneur and a friend of Mr. Clinton’s, was introduced by a Clinton aide to Colombian President Alvaro Uribe at a 2005 philanthropic event organized by Mr. Clinton. Mr. Giustra has met with Mr. Uribe several times, and last year, a company advised by Mr. Giustra’s firm acquired interests in Colombian oil fields.

Mr. Giustra has traveled often with Mr. Clinton, and has pledged more than $130-million to his philanthropic activities, including the Clinton Global Initiative and the William J. Clinton Foundation.

“Have I used my relationship with President Clinton to benefit me or my business? No,” says Mr. Giustra in a written reply to questions from the Journal. “Have world leaders bent over backwards for me because I’ve accompanied President Clinton on [philanthropic] visits . . .? No. Do I resent any implication to the contrary? You bet.”

The relationship between Mr. Giustra and Mr. Clinton was recently examined in a New York Times article about business dealings in Kazakhstan.

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