Conservative Indo-Canadian MP Gurmant Grewal has taken stress leave even as his allegations that the Liberals offered him inducements to switch parties to keep the government from collapsing last month are being probed.

"...Grewal informed me in writing that he would be stepping down from his position as co-chair of the Standing Joint Committee for the Scrutiny of Regulations, while the current investigation takes place. I look forward to Gurmant reassuming these responsibilities when these matters are resolved," Conservative Party leader Stephen Harper said in a statement.

The opposition leader's statement also said: "Subsequently, I have spoken with Gurmant. I have been aware that for some days now he has been feeling significant personal pressure. As a result, he and I agreed that he should take a temporary stress leave from his parliamentary responsibilities."

Grewal, an MP from Newton-North Delta riding, is under pressure as a growing number of audio experts believe the secret tapes he released May 31 to the Royal Canadian Mountain Police containing conversations he had with Tim Murphy, chief of staff to Prime Minister Paul Martin and Health Minister Ujjal Dosanjh.

Grewal's wife Nina, a Conservative MP from Fleetwood-Port Kellis, whose name is also mentioned in the alleged deal, claimed June 8 that she had nothing to do with the secret tapes.

She told the Toronto Star in an interview, "Nobody approached me, I wasn't part of any negotiations."

In the meanwhile, in a new development, Grewal is being investigated by Air Canada. The national carrier is scrutinising allegations that Grewal approached strangers at Vancouver International Airport a few days ago and asked them to take a package to Ottawa, a violation of security regulations.