THE CITY OF BOSTON AND WYNN RESORTS are now fighting over whether the Las Vegas company filed a required application with the municipality’s Public Improvement Commission to make road improvements in Sullivan Square near the site of its proposed $1.8 billion casino.

Wynn says it filed the necessary paperwork, but Boston officials say they never received a proper application. It may sound like nothing more than bureaucratic busywork, but city officials say Wynn’s eastern Massachusetts casino license should be revoked if the company failed to file an application by mid-February. Indeed, officials from the Massachusetts Gaming Commission have stated that the application was a condition of the license and needed to be filed within 90 days of the November 7, 2014, license award.

In a letter to Wynn on Monday, Gina N. Fiandaca, commissioner of the Boston Transportation Department, said the casino developer had never filed an application to the Public Improvement Commission despite its repeated claims to the contrary.

“The documents submitted by Wynn on Jan. 30, 2015, are the only documents that the PIC has ever received from Wynn,” Fiandaca wrote. “The engineering report and coordination plans omit virtually all the required components of a valid permit application. Despite Wynn’s characterization, the documents it submitted do not constitute an application. Wynn’s submission is, at best, merely an update on its continually evolving proposals for the area.”

Wynn responded on Tuesday, sending a letter to Fiandaca suggesting that the materials it submitted were sufficient. Robert DeSalvio, president of Wynn MA LLC, said the Public Improvement Commission’s checklist and process description don’t refer to a formal application requirement. He said Wynn’s engineering report and coordination plan comply with the first three steps on the Public Improvement Commission’s checklist.

“The fourth step in the process is to consult with PIC’s legal counsel to begin drafting the license, maintenance, and indemnification agreement. This step requires the cooperation of the Public Improvement Commission and has not yet commenced,” DeSalvio wrote. “We remain available to meet at any time to move this forward. Please propose some dates and times.”

A meeting is unlikely, given that Boston Mayor Marty Walsh is suing the gaming commission to block its license award to Wynn and the mayor is refusing to send city officials to meetings ordered by state environmental officials on developing a long-term solution to traffic problems in Sullivan Square.

DeSalvio notes in his letter that the “poor operation of Sullivan Square under existing conditions” has been a matter of concern to state officials and neighborhood residents for many years. He said Wynn has proposed spending between $35.9 million and $55.9 million on infrastructure improvements in the area, which he said would be one of the largest privately funded mitigation projects in Massachusetts.

“Given the magnitude of the existing problem, the complexity of the proposed long-term solution, and the significant investment that Wynn has committed, we appreciate the challenges that the Boston Transportation Department is experiencing in processing our submission,” he wrote.