Prime Minister Stephen Harper is rejecting Liberal calls for an inquiry into payments received by former prime minister Brian Mulroney.

Harper said Friday that he does not have the authority to launch investigations into former prime ministers.

"I think this call by the Liberal Party is really extraordinarily dangerous. Do they really want to say that I, as prime minister, should have a free hand to launch inquiries against my predecessors?" he said in Halifax, where he was addressing an aboriginal conference.

Recent news reports say Mulroney waited years before paying taxes on $300,000 he received from German-Canadian Karlheinz Schreiber in a deal made shortly after leaving office.

According to a report in The Globe and Mail, Mulroney was delayed in paying the taxes because of a "cataclysmic event" in his life in November 1995.

The event refers to an RCMP letter to the Swiss government, which falsely accused him of a crime in the purchase of Airbus planes by Air Canada.

In 1997, the Chretien government was forced to apologize and pay Mulroney a $2.1 million settlement in a defamation suit.

"Mr. Mulroney got paid $2 million, unfortunately paid by the taxpayers of Canada," Harper said.

While taking questions from reporters, Harper suggested that if the Liberal Party wanted him to launch politically charged investigations, he could theoretically start with past Liberal dealings -- including former prime minister Jean Chretien's involvement in the controversial sale of golf courses and Paul Martin's involvement with Canada Steamship Lines while he was prime minister.

"This is not a route that I want to go down, and I don't think if the Liberal Party thought twice about it, it is a power they would want to give me," Harper said.

Liberal Leader Stephane Dion said during question period on Thursday that the new information warranted another look.

"Will the prime minister take every step necessary regarding this disturbing information about Brian Mulroney to get to the bottom of this matter?" Dion asked.

"The current prime minister owes the institution he represents a duty to shed full light on this issue. Will he do that? Will he set up a commission of public inquiry?"

A statement issued by Mulroney's spokesperson points out that the RCMP, after years of investigation, failed to find any evidence to substantiate allegations of wrongdoing.

Schreiber is currently in a Canadian jail awaiting extradition to Germany on unrelated criminal charges.

Earlier this month, Schreiber lost his latest legal challenge to avoid deportation to Germany.

The Supreme Court of Canada declined to hear an appeal by Schreiber, 73, who has been fighting extradition since 1999.

With files from The Canadian Press