MGM Resorts has dropped a lawsuit over the Mashantucket Pequot and Mohegan tribes’ plan to develop an East Windsor casino, a project shelved as part of the gaming-expansion agreement negotiated earlier this year between Gov. Ned Lamont and the tribes.

The agreement formed the basis of legislation passed by the legislature and signed into law by the governor.

In a filing over the weekend in U.S. District Court for the District of Columbia, MGM Resorts Global Development and Blue Tarp Redevelopment, another MGM entity, dismissed “without prejudice” their suit against the U.S. Department of the Interior over the department’s approval of state-tribal gaming agreements that facilitated the East Windsor project.

The state and the tribes were granted intervenor status on the defendants’ side and had joined the Interior Department in seeking the suit's dismissal.

None of the parties to the suit would comment on MGM Resorts' withdrawal of it.

MGM Resorts had long sought to prevent the tribes from pursuing their plan to develop a casino in north central Connecticut to protect the tribes' existing casinos — Foxwoods and Mohegan Sun — from competition from MGM Springfield, the Massachusetts casino MGM opened in 2018.

The East Windsor casino site is about 12 miles from MGM Springfield.

In its 2019 suit, MGM Resorts claimed amended gaming agreements between the state and the tribes are unprecedented and illegal and put MGM at a competitive disadvantage in bidding to operate a commercial casino in the state. Earlier, MGM had proposed the state adopt an open, competitive process for allowing another Connecticut casino and had proposed building one in Bridgeport.

The new law authorizing the tribes and the Connecticut Lottery Corp. to provide sports betting and the tribes to provide online casino gaming contains a provision preventing the tribes from pursuing their East Windsor project for at least a decade. Lamont had sought such a provision to render the MGM lawsuit moot.

MGM still could be seeking to operate in Connecticut.

The Las Vegas-based company, which owns BetMGM, an online sports-betting operator, in partnership with Entain, expressed interest earlier this year in operating in the state. The Connecticut Lottery Corp., which is in the process of choosing a sports-betting operator with which to partner, concluded a request-for-proposals process Friday, having received responses from five operators, according to a spokeswoman.

Asked if BetMGM was among the five bidders, Tara Chozet, the spokeswoman, said she could neither confirm nor deny the identity of any of the bidders.

BetMGM operates online sports betting in a growing number of states, including Colorado, Indiana, Iowa, Michigan, Nevada, New Jersey, Pennsylvania, Tennessee, Virginia and West Virginia, as well as Washington, D.C.

The lottery is expected to choose a sports-betting operator by June 28, though it won't name the operator until a contract has been signed.

b.hallenbeck@theday.com