WINNIPEG - Manitoba's governing NDP says it would welcome an investigation by the auditor general into the construction of Winnipeg's CFL stadium amid allegations it was rushed, poorly planned and overbudget.

Premier Greg Selinger said he's not afraid of any audit into the construction of Investors Group Field and defended the project, which is now the subject of a lawsuit.

"The auditor general is an independent officer. They are completely free to investigate any of these things. We have no problem with that," Selinger said Thursday.

"We're very proud of the building. We think it's making a big contribution to Winnipeg."

The owners of the stadium, which is to hold the Grey Cup this fall, have filed a lawsuit claiming the architect and builder should be made to pay for extensive repairs the owners allege are due to faulty design and construction.

The stadium has been plagued by leaks, insufficient insulation to keep plumbing working in winter and poor drainage. It also needed immediate renovations to make it usable for concerts and its press box was unheated.

A construction company, in turn, alleges the owners and the provincial government approved the design without regard for such issues. It also claims the project may have been rushed.

None of the allegations put forward by either side has been proven in court.

The stadium, which was initially budgeted to cost $115 million, cost $209 million and was completed in 2013.

Manitoba's Opposition has been calling for the auditor general to look into whether the NDP rushed construction of the stadium and whether the project made good use of tax dollars.

Selinger said he can't comment on the lawsuit but "obviously everyone wanted to get it built" because the old stadium "had some real risks attached to it."

Progressive Conservative Leader Brian Pallister said the government appears to have used the stadium project as a 2011 election campaign prop. Taxpayers are ultimately footing much of the bill and deserve some answers, he said.

"We know that rushing a quarterback can be a really good thing, but rushing a construction project tends not to be," Pallister said. "What we were asked to invest in is something that we have not yet received."

Infrastructure Minister Steve Ashton said it's not unusual for large construction projects to run into difficulty. The NDP didn't rush the project since the construction was actually delayed by a year, he said.

"The bottom line is, it's constructed now and it's a good facility for Manitoba."