Federal opposition parties voted Thursday to open a broad parliamentary probe into allegations involving Brian Mulroney and Karlheinz Schreiber, calling for both the former Tory prime minister and the German-Canadian businessman to testify as soon as possible.

The motion by the federal ethics committee came as Schreiber asked the Supreme Court of Canada to reconsider his pending extradition to Germany.

The committee proposed that Schreiber, who is awaiting extradition to Germany in the Toronto West Detention Centre, should publicly testify as early as next week, on Nov. 27 and Nov. 29. Mulroney will be called before the committee on Dec. 4 and has been slated for three days of testimony.

While committee chair Liberal MP Paul Szabo said he wants the testimony to be public, he told CBC News that he couldn't rule out the possibility that testimony could be behind closed doors.

But NDP MP Pat Martin, another committee member, said he would oppose an in camera session.

"The whole purpose was so that Canadians could get some straight answers to some fairly simple questions and we want both sides of this whole sordid mess to be openly and publicly explained. So I would certainly resist and oppose going underground."

The committee's probe will include a review of Mulroney's $2.1-million settlement from the federal government in 1997 over his libel suit regarding the so-called "Airbus affair" — in which millions of dollars in secret commissions were paid in respect to the sale of jets to Air Canada.

The committee will also review new allegations that have come to light in the wake of a lawsuit Schreiber has launched against Mulroney.

Schreiber is suing Mulroney to recoup $300,000 in cash payments he handed out to the former prime minister to enlist his help in establishing a pasta business and a light armoured vehicle factory. Schreiber contends that Mulroney did not provide the services, something Mulroney disputes.

Schreiber alleged in an affidavit that the deal was struck two days before Mulroney left office as prime minister.

Schreiber also alleges that a Mulroney adviser asked Schreiber to transfer money in connection with Air Canada's 1988 purchase of Airbus planes to a Mulroney lawyer based in Switzerland.

None of the allegations against Mulroney has been proven in court, but they spurred Prime Minister Stephen Harper to call a public inquiry into the affair.

The probe will also look into what Harper knew about letters sent to his office by Schreiber.

The Liberals have publicly insisted that the committee's probe should focus on Harper's handling of the situation.

"We have always said that we want a thorough examination but one that includes very specifically the behaviour of the Harper government," Liberal House leader Ralph Goodale said.

But some Liberal MPs have expressed worries about a wider investigation.
 
"When you get into this kind of investigation, if you stray too far, you're duplicating the work of the inquiry without the resources of the inquiry and without the safety net for the people whose names may be brought forward in an accusatory way," Liberal MP Robert Thibault told the Ottawa Citizen.

The Conservatives, who voted against the plan, have said they are concerned the probe could turn into a witchhunt.

Schreiber asks top court to reconsider extradition

Meanwhile, Schreiber filed for leave to appeal to the Supreme Court on Thursday to reconsider a recent decision by the Ontario Court of Appeal not to intervene in his extradition order. He faces extradition to Germany on Dec. 1 to face fraud charges.

In a statement Thursday, Schreiber said there should be "no urgency at all" to surrender him because there is no obligation to deport a Canadian national under Canada's extradition treaty with Germany.

"In spite of the politically motivated vendetta against me, I will continue to fight for fundamental justice to prevail in Canada."

The CBC's Rosemary Barton said that because Schreiber is in jail, the ethics committee may have to take the rare step of asking Parliament to issue a House order to get him temporarily released to testify.

With files from the Canadian Press