BOSTON — The city of Boston refused to accept a $1 million check to help offset the impact of the resort casino planned for neighboring Everett, gambling giant Wynn Resorts said Wednesday.

Boston sued the Massachusetts Gaming Commission earlier this week, seeking to stop the $1.6 billion project from going forward unless residents in the city’s Charlestown neighborhood are given a vote.

Wynn said the $1 million check was delivered to the commission after Boston declined it, and is expected to be held in escrow for the city. The payment is supposed to be used to support nonprofit organizations and other programs in Charlestown, the neighborhood located directly across the Mystic River from Wynn’s planned waterfront development.

The payment is the first in a minimum $56 million financial compensation package for Boston that was ordered by the gambling commission after Mayor Martin Walsh’s administration refused to participate in negotiations with the Las Vegas casino giant.

The compensation package orders Wynn to spend a total of $31 million toward improving traffic in heavily congested Sullivan Square — a key concern of the city. It also calls for $24 million in total annual payments to Boston and includes a provision that if Wynn fails to meet its traffic projections, it will pay the city up to $20 million more in fees.

A gambling commission spokeswoman said the agency will hold the check, which was made out to the city until Boston officials are ready to claim it.

Walsh’s administration responded: “The payment Wynn is referencing is a condition of Wynn’s agreement with the Gaming Commission, not with the City. If Wynn were to make a payment related the agreement, it would be made to the Gaming Commission, not to the City of Boston.”