Saskatchewan Premier Brad Wall's comments about speaking fees given to Justin Trudeau have upset the federal Liberal party, and it's calling for an apology.

Wall, however, said Friday he stands behind his comments, insisting he is merely seeking accountability from Trudeau over a $20,000 fee collected for a speaking engagement in Saskatoon in 2012.

"Hopefully he might consider reimbursing the [Saskatoon] literacy conference and I understand other charities that have paid the $20,000 fee to hear him speak," Wall told CBC News Friday.

Wall said he believes it would be inappropriate for Trudeau to accept such fees and use the money to bankroll his successful bid for leadership of the Liberals.

"I asked whether the money he earned at the literacy conference was used to help finance his leadership campaign," Wall said. "I also suggested Mr. Trudeau reimburse the organizers of the Saskatoon conference."

In a news release issued Friday, an official from the Liberals characterized Wall's comments as a smear against Trudeau.

"Premier Wall needs to immediately apologize for this smear," the release said, and suggested Wall was keen to enter federal politics as a Conservative. "It looks like the race for Mr. Harper's job is on."

Wall responded to that, saying he was only seeking accountability.

"If Mr. Trudeau is saying that none of the thousands of dollars he charged to charities like the literacy conference in Saskatoon indirectly or directly aided his campaign for the Liberal leadership, then I accept him at his word," Wall said.

"There is no apology," he added. "I asked questions on accountability and stated my opinion that these fees shouldn't be charged by elected officials."