SASKATCHEWAN (CBC) - The proposed domed stadium in Regina could cost a lot more than was previously anticipated, the New Democrats say.

A study is under way to see if building a new open-air home for the Saskatchewan Roughriders is feasible.

For months, government officials discussing the proposal have said it could cost $350 million.

However, on Thursday, NDP MLA Warren McCall told the legislature he's heard the price has risen to as much as $600 million.

"What we're hearing from the different community groups that are being consulted is that the numbers the consultants are using are $480 to $600 million," McCall said in the legislature.

"In terms of the many people that have been talked to on it so far, those are the numbers that are coming back."

The consultants involved in the $1 million study are expected to report back to the government in January or February.

Before they do, Cheveldayoff said, the government wants to hear ideas from private companies.

"What we are going to do is go out to the private sector and ask for expressions of interest," Cheveldayoff said. "We want to open it up to any private sector individuals."

Asked about the potential $600 million price tag, Cheveldayoff said that was news to him.