Nashville Mayor Megan Barry's administration has reached a preliminary deal with a local investor group led by prominent businessman John Ingram for the financing of a Major League Soccer stadium at the city's fairgrounds.

Now, they plan to ask the Metro Council to approve it.

► Related:MLS in Nashville: Vandy football won't move stadium off-campus

A special council meeting is set for Monday at 3 p.m. for the mayor's office to present details of the stadium financing proposal.

Barry spokesman Sean Braisted confirmed the two sides have come to terms, although he said some minor details are still getting worked out. Barry has said she will put forward a "private-public" financing deal for the stadium, with an emphasis on the private investment.

Particulars of the proposed financial arrangement have not been released.

The council would have to sign off on the proposal at a later meeting for the deal to move forward.

“We welcome the opportunity to discuss with council a private-public partnership that will put Nashville in the best position to win a Major League Soccer expansion team for the city," Clint Brewer, spokesman for MLS2Nashville, said in a statement.

Nashville is one of 12 cities bidding for four expansion slots that MLS wants to fill. The league plans to award two cities in December, a timeline that has expedited Nashville's efforts to land a team.

► More:MLS commissioner: Nashville 'high on the list' for expansion team

Barry's administration and the Ingram-led group have negotiated a funding package in the weeks since the soccer group unveiled plans for a 30,000-seat MLS stadium on Aug. 14.

Free market think tank calls for referendum on stadium

After The Tennessean reported Thursday that a preliminary deal had been struck, the conservative think tank Beacon Center of Tennessee called for a public referendum that would let Nashville voters decide whether tax dollars should go toward the stadium.

"The Beacon Center is against the city of Nashville forcing taxpayers to fund a private soccer stadium," the group's statement reads. "However, we think that the residents of the city should be the ones to make the decision on whether their money should be spent on any professional sports stadium.

"That is why the Beacon Center is calling for a referendum, triggered by the city council, to allow voters to decide this very important issue if the city of Nashville is selected by the MLS."

► More:Nashville MLS group unveils first look at stadium proposed for fairgrounds

Barry is not required to hold a public referendum for approval of the stadium's financing, and no council members have said they plan to push one.

No price tag yet on new soccer stadium

The city-owned Nissan Stadium, home of the NFL's Tennessee Titans, was built after Nashville voters in 1996 approved a public referendum for the $292 million project.

Neither the mayor's office nor the investor group have said how much the MLS stadium would cost to build, but comparable MLS stadiums range between $200 million and $300 million.

► More:Nashville Soccer Club to play inaugural season at First Tennessee Park

Vanderbilt University had considered the possibility of sharing the proposed new stadium for the school's home football games. But the university announced on Wednesday that it will remain at its on-campus Dudley Field.

Reach Joey Garrison at 615-259-8236, jgarrison@tennessean.com and on Twitter @joegarrison.