BOSTON — Mayor Martin Walsh on Thursday asked state gambling regulators to halt the process for awarding the Boston-area casino license until after a November vote on the casino law.

Walsh said he doesn’t want to continue spending taxpayer money on negotiating financial compensation deals with Mohegan Sun and Wynn Resorts – the two companies still vying for the Boston-area license – while the law itself is uncertain.

“We’re facing an unprecedented situation here in Massachusetts right now,” Walsh said. “If the voters choose to repeal the law in November, all parties involved will risk losing precious time and millions of dollars for nothing.”

The state’s highest court on Tuesday cleared the way for the repeal question to be placed on the ballot, after state Attorney General Martha Coakley, who is running for governor, initially declared the referendum unconstitutional.

The Massachusetts Gaming Commission has said it intends to continue with the licensing process, despite the court ruling. On Thursday, it confirmed it had received Walsh’s letter but had not yet reviewed it.

The Boston-area license is one of three regional casino licenses the commission is authorized to award.

The five-member panel this month awarded the state’s first casino license to MGM Resorts International for an $800 million casino proposed for downtown Springfield. It has also already awarded the state’s lone slot parlor license to Penn National Gaming for its Plainridge harness racing track project in Plainville.

Walsh’s office had been negotiating with Mohegan Sun and Wynn Resorts on deals to compensate Boston for impacts to traffic and city services.

The city and Wynn had set a Wednesday deadline to finalize a deal. Mohegan Sun and the city had set a Friday deadline. Walsh on Thursday said the city and the casinos, under state law, will go to arbitration in about five days if no deal is reached.

The Boston-region gambling is expected to be awarded in late August or early September.

Wynn proposes a $1.6 billion casino in Everett and Mohegan Sun proposes a $1.3 billion one on the Suffolk Downs horse racing track in Revere.

Mohegan Sun said in a statement that it was “shocked and extremely disappointed” with the mayor’s announcement.

“We have been fully cooperative with Mayor Walsh’s administration and negotiating in good faith with the City to agree on a surrounding community agreement. … Two licenses have already been awarded and there is absolutely no reason not to continue fulfilling the promise of this landmark legislation.”

Revere Mayor Daniel Rizzo, in a statement, agreed: “A timeline has been announced and they should stick with it.”

Bill Mulrow, board chairman at Suffolk Downs, said he was “dismayed” by the mayor’s request, and that additional delays in the licensing decision “will put our operation and our workforce at risk and we urge the Commission to stick to its announced timeline.”

But Republican gubernatorial candidate Charlie Baker, who is against repealing the casino law, said Walsh’s call for a delay until November is the “best path forward.”