Ontario's auditor general has been asked to probe the Ontario Lottery and Gaming Corp.'s controversial expansion plans and last year's cancellation of the slots-at-racetracks program.

A legislative committee approved the audit today, which will examine whether there are any secret or one-off deals of casino hosting payments to municipalities.

The investigation will also look into the provincial Liberal government's cancellation of the $345-million-a-year share of slot machine revenues earmarked for racetracks.

OLG's president and CEO Rod Phillips said they would "support the AG's review in every way we can and we look forward to working with his office."

Last May, the Crown corporation identified 29 "gaming zones" that cover every area of the province, asking prospective developers to submit proposals.

As part of the investigation, the legislative committee also directed Auditor General Jim McCarter to look into the OLG's plans for gaming facilities, bingo halls, online gaming and lotteries.

McCarter said work could start almost immediately and it won't delay probes into the cancellation of the Oakville gas plant during the 2011 election campaign, and the selling-off of the Ontario Northland Transportation Commission.

His report into the cancellation of the Mississauga gas plant in 2010 will be released on Monday.

McCarter is leaving his post May 1.

With files from The Canadian Press