TORONTO - Premier Dalton McGuinty says he's willing to consider putting up some provincial cash to build a pedestrian tunnel to Toronto's island airport.

But the province needs a formal proposal before the project could be considered for government funding, he said Monday.

"I'm not going to say yes or no because there's a process for these kinds of things," McGuinty said during a visit to the University of Waterloo.

"I think we'd have to see what pots of money (there are) for which the proposal might qualify and see if there's any money in those pots. But I think it's something that's worthy of consideration."

The Toronto Port Authority is moving ahead with plans to build the tunnel under the lake that would connect travellers with the airport, which is currently accessible by ferry.

The authority issued Monday a formal request for proposals to conduct an environmental assessment, the first step in any major project, the Toronto Star reported.

Port Authority chairman Mark McQueen told the newspaper the project does meet the rules for federal infrastructure funding.

Ottawa hasn't said if they plan to contribute any funding for the $38 million project.

Any plan for a walkway may draw the ire of Toronto Mayor David Miller, who campaigned in 2003 to kill a proposed bridge to the island airport.

The tunnel would be eight metres wide, four metres high and outfitted with moving sidewalks for passengers of upstart Porter Airlines.