CALGARY - Natural Resources Minister Lisa Raitt is brushing aside accusations about expenses she claimed while serving as president of the Toronto Port Authority.

She would not comment on the specifics of the allegations, but says she's caught in the middle of a dispute between two feuding factions of the arms-length government body.

A Toronto Star report alleged that Raitt signed off on her own expenses at least once -- for a $3,000 trip to London, England -- during her term as port president. Toronto lawyer Michele McCarthy, a former chair of the port's board of directors, told the newspaper that she refused to sign off on the trip, which was not pre-approved, so Raitt signed herself.

"It's unfortunate that it features prominently in a piece -- these kinds of accusations," Raitt in an interview in Calgary with The Canadian Press on Friday. "This is a board issue, this is certain directors and other directors having a disagreement about a time and place and discussing it through the media."

The Star obtained documents suggesting that Raitt racked up expenses of almost $130,000 and signed off on a number of claims, including a $9,000 lunch for 50 people at a Toronto steakhouse.

The port authority has responded to the accusations by pointing out that Raitt's trip to London and its proposed cost was approved by the board as part of the 2008 budget process and the lunch was pre-approved and placed under the category "Promotion."

"What's happening right now is we have a TPA board matter, and clearly we're talking about a point in time when there was unrest within that port in terms of the board and it's continuing," Raitt said. "You know there's two sides to every story and you've got one set of directors who are giving their side right now and there's another set of directors that I'm sure will come forward and talk about their side."

The Liberals are demanding an audit of Raitt's expenses during her stint as president.

Paul Szabo, the Liberal chair of the House of Commons ethics committee, added Auditor General Sheila Fraser on Thursday to the list of independent parliamentary watchdogs he has asked to investigate alleged ethical lapses by Raitt.

In a letter Thursday, Szabo asked Prime Minister Stephen Harper to grant Fraser a mandate to conduct a special audit of the port authority's operations during Raitt's tenure. The authority is funded by the federal government.

In the Commons, Szabo accused Raitt of unethical conduct and the government of executing a "shameful cover-up" of the affair.

There was no cover-up, said Raitt.

"First of all, I had a fiduciary duty at the Toronto Port Authority. I discharged it and the only thing I would say that is of concern is this release of documents that are private to the Toronto Port Authority and within the confines of the boardroom," Raitt explained. "For me it's about matters of the board. These are matters and any good CEO will tell you don't meddle in the matters of the board."

As for the call for an audit, Raitt said there have been plenty at the port authority, not just for when she was in charge.

"The port authority is audited every year and they'll be preparing for their mandate's special exam." she said.

"All the time we had audits in there. We had forensic audits, we had special appointees of the government who went in to look at stuff."