Backers of a proposed professional soccer stadium in Minneapolis will lose their exclusive right to purchase industrial land near downtown on Monday, and the owner of the site says he won't entertain future offers from the group.

This new development could pose a significant blow to Minneapolis' chances of securing Minnesota United, which sought city property tax breaks to construct a $150 million stadium near the city's Farmers Market. The team has grown interested in a site near the Midway shopping mall in St. Paul, where there is more political appetite for a tax deal.

"The only thing that can change is they have a check on my desk on Monday morning. In reality, I doubt it," said Robert Salmen, who owns two of the three parcels on Royalston Avenue that would be used for the stadium — about 80 percent of the proposed site.

A development entity representing Minnesota United team owner Bill McGuire secured the yearlong option at this time in 2014. Salmen said once it expires Monday, he does not plan to sell to McGuire.

"We have no interest. … Even if they're interested at this point, we're not going to proceed," Salmen said. "We're done with it."

He added that they have had "no written communication for a year."

McGuire's investment group has been looking for a place to build a stadium since receiving a Major League Soccer franchise this March — contingent on a new facility. A team spokesman did not immediately return a message seeking comment Friday afternoon. The group includes Glen Taylor, who owns the Star Tribune.

The property has several long-term tenants, including Target, which uses it for photo shoots. Having it under option is limiting, Salmen said, in part because it means he cannot lease vacant space.

Salmen said he originally agreed to the option in part because he was concerned about the property being taken by a government, under eminent domain laws. His advisers now tell him that he is protected, because he was cooperative.

"I've got developers knocking on my door every day," Salmen said. "When I want to sell, or if somebody makes a stupid offer, I'll sell. But you know what? That's not going to happen for a while."

The mayor and City Council in St. Paul have said publicly they will grant a property tax exemption if the stadium is built at the Midway site. Gov. Mark Dayton said on the radio Thursday that he supported allowing St. Paul to exempt the property from taxes, which would require a state signoff.

Minneapolis Mayor Betsy Hodges, by comparison, said in April that she was firmly opposed to such a tax break. Most recently, the Minneapolis deal had shifted to Hennepin County, where two commissioners proposed a plan to use excess Twins ballpark taxes to pay for infrastructure costs. The stadium would be publicly owned, freeing it and team owners from property tax obligations.

But it is unclear if that will matter if the land is no longer available.

"St. Paul is moving quickly forward," said Minneapolis City Council Member Jacob Frey, who has been a strong advocate for landing the stadium. "It would be a shame if we lost this opportunity."

Eric Roper • 612-673-1732

Twitter: @StribRoper