Portland Mayor Keith Wilson said the city's negotiations with the Trail Blazers over a Moda Center renovation are "fragile" and carry no guarantee the team stays.

"What I want everybody to know is that this is fragile," Wilson told KOIN 6 on Thursday, Sept. 17. "There is no certainty at all."

The comments mark the mayor's most candid public assessment of the arena standoff.

Wilson said he is "absolutely concerned" about the timeline. The city needs Blazers owner Tom Dundon to sign a 20-year lease by Dec. 31, or Oregon's $365 million commitment to the renovation expires.

Portland's City Council voted 8-4 on Aug. 12 to approve a term sheet pledging $120 million toward the renovation, which carries an estimated $600 million price tag. But the city still has not identified a funding source for that $120 million. The city's own resolution describes the money as coming "from sources yet to be confirmed."

The state's $365 million and Multnomah County's $88 million round out the public share, totaling $573 million. Under the term sheet, the Blazers would pay $3.17 million per year in rent, rising up to 3% annually, totaling more than $85 million over 20 years.

Wilson identified three sticking points. The issues are the renovation's first-class standard, rent and union terms. He said Dundon is personally involved in talks, along with a team on his behalf, and that progress is happening behind the scenes.

The mayor's tone Thursday was sharply different from a statement he emailed to OPB on Tuesday, Sept. 15. In that statement, Wilson wrote that "Portland is resurgent" and "the future of the Blazers is here."

His shift came after NBA Commissioner Adam Silver's remarks the same day. Silver said at a press conference after the NBA Board of Governors meeting in New York that he would consider it "a failure" if the Blazers left Portland. Silver called on all parties to "lower the temperature" and said the Moda Center ranks near the bottom of NBA arenas.

Wilson echoed that language Thursday, calling a potential exit a failure for the NBA, the Blazers' owner and the city, county and state.

Earlier in September, City Administrator Raymond Lee met with Dundon in Texas. Sports Business Journal reported one source called the sit-down "a decent conversation," while another described it as "more of an introduction than a formal negotiation." Wilson called the meeting "a huge deal" for building trust.

Dundon has not made any public statement about the negotiations. He purchased the Blazers for a reported $4.25 billion. The team has played in Portland since 1970 and moved into the Moda Center in 1995. The arena has never undergone a comprehensive renovation.

Lease negotiations are expected to continue through November, with a final agreement due before City Council by Dec. 31. The WNBA's Portland Fire, which also plays at the Moda Center, would be affected by any deal or relocation.