A federal agency revived the East Windsor casino project Thursday, announcing it will publish notice next week of its approval of the Mashantucket Pequot Tribe’s amended gaming agreements with the state — a legal requirement crucial to the process.

It marked a major turn in the Mashantucket and Mohegan tribes’ yearslong drive to protect their respective southeastern Connecticut casinos, Foxwoods and Mohegan Sun, from the competitive impact of MGM Springfield, the nearly $1 billion resort casino MGM Resorts International opened last summer in western Massachusetts.

In 2015, the tribes formed a partnership, MMCT Venture, to pursue the project, which the state authorized in 2017. Interior recognized the Mohegans’ amended gaming agreements with the state last year.

Las Vegas-based MGM Resorts indicated Thursday it will continue fighting to block the East Windsor project.

“Today is a great day for the Mashantucket Pequot Tribal Nation and the State of Connecticut, especially given our 400-year history together,” Rodney Butler, the Mashantucket tribal chairman, said in a statement. “... Now that the approval of our amendment is secured and our exclusivity agreement with the State of Connecticut is reaffirmed, we will move forward with construction on Tribal Winds Casino in East Windsor and preserve much needed jobs and revenue.”

Crews cleared the construction site last spring, leveling the Showcase Cinemas building that stood there, off Exit 45 of Interstate 91.   

In its announcement, the Interior Department acknowledged that up until this month it “did not approve or disapprove” the proposed amendments to the Mashantuckets’ “procedures” and memorandum of understanding, which the tribe had submitted in August 2017.

“After further consultations with the Tribe,” the announcement says, Tara Sweeney, Interior’s assistant secretary of Indian affairs, approved the agreements in recent days. Interior will publish notice of the approvals Monday in the Federal Register, at which time they will take effect.

Gov. Ned Lamont’s director of communications, Maribel La Luz, issued a statement hailing Interior’s action.

“Approval of these amendments ensures that any state law authorizing MMCT to operate a commercial casino off of the tribal reservations will do no harm to the state’s existing revenue sharing agreements with the tribes,” La Luz said. “We remain committed to working with the tribes toward a global resolution of all outstanding legal issues or obstacles that may arise out of this decision, including any lawsuits third parties may bring against the state law that now authorizes MMCT to operate a commercial casino in East Windsor.”

The revenue-sharing agreements require the tribes to pay the state 25 percent of their casinos' slot-machine revenues.

While seeking to block the East Windsor casino, MGM Resorts has pushed state lawmakers to establish a competitive-bidding process among gaming operators interested in building a casino in the state. MGM Resorts has proposed a Bridgeport casino.

“The Attorney General’s office has repeatedly warned, as recently as last year, that pursuing a no-bid approach in East Windsor would expose Connecticut to significant legal risks,” Uri Clinton, an MGM Resorts executive, said in a statement. “As MGM has always stated, we will continue to pursue all legal options, including litigation, to defend our right to compete in Connecticut. ... MGM remains steadfast in our view that Bridgeport is the best location in Connecticut for a commercial casino if the state is to maximize jobs, economic growth, tourism, and revenue — and a transparent, competitive process is in the state’s best interest.”

A legislative committee this week approved a competitive-bidding casino bill as well as another measure that would eliminate the requirement that the tribes secure federal approval of the gaming amendments related to the East Windsor project.

Sen. Cathy Osten, the Sprague Democrat who championed the so-called East Windsor “fix,” said Interior’s latest approval renders the proposed legislation moot.

“I can’t wait to go to the (East Windsor) ribbon-cutting,” she said.

Sen. Paul Formica, an East Lyme Republican, also celebrated Thursday’s development, crediting Interior “for doing the right thing down there in Washington.” He said he expected MGM Resorts to continue doing whatever it can to keep the East Windsor casino from materializing.

“They’ve been spending millions of dollars in their effort to derail East Windsor and gain a foothold in Connecticut without following the law,” he said. “I don’t expect them to stop now.”

The Mashantuckets and the state sued in federal court to compel Interior to act on the tribe’s gaming amendments, alleging that former Interior Secretary Ryan Zinke succumbed to undue political influence in failing to approve them. The tribe and the state allege that MGM Resorts lobbied Nevada lawmakers who pressured Zinke and others.

U.S. Sen. Richard Blumenthal, D-Conn., and other members of the state's congressional delegation called for Interior’s inspector general to investigate the department’s handling of the tribes’ gaming amendments. Zinke, the subject of probes into that and other matters, resigned at the end of 2018. The Washington Post later reported that a grand jury was looking into whether he lied to federal investigators.

b.hallenbeck@theday.com