According to a letter filed on Tuesday to a judge, at least six major groups of victims of the Sept. 11, 2001, attacks have struck a tentative deal to divide about $3.5 billion in Afghan central bank assets they are trying to seize to pay off legal claims against the Taliban.

Some families would receive a much larger payouts than others, because another major group is not part of the deal. The central bank funds deposited in the Federal Reserve of New York can be used to pay off the Taliban's legal debts.

The disclosure of the framework agreement raised the possibility of avoiding a potentially ugly fight among different groups of Sept. 11 victims over who gets the money. A legal and politically dramatic attempt by widows, orphans and other relatives of attack victims to seize the Afghan funds could be removed.

The lawsuits filed years ago by Sept. 11 victims seek billions of dollars in damages from a range of defendants, including Al Qaeda and the Taliban. The defendants were declared liable by default when they failed to show up.

The rulings were symbolic until last fall, when the government of Afghanistan collapsed during the Taliban takeover. The Federal Reserve of New York blocked access to an account for the Afghan central bank, which had $7 billion in deposits.

Lawyers for a group of Sept. 11 victims persuaded a judge to send a marshal to serve the Federal Reserve of New York with a death sentence.

A group of State Department victims of an attack linked to the Taliban began the process of trying to seize some of the funds to pay off a $137 million judgment debt.

The Biden administration wanted to weigh in on what would serve the national interest. President Biden used emergency power to seize half of the central bank's assets in February in order to help the Afghan people. The White House left half of the money for the Sept. 11 families.

There had been controversy around that effort. There is a dispute about whether the Afghan funds should be used to pay off Sept. 11 families in Afghanistan. If a court were to decide that the funds could be used to pay off the Taliban's default judgment debts, the other dispute centered on how they should be allocated.

The group of about 150 people, linked to 47 estates of the nearly 3,000 people killed in the 9/11 attacks, was trying to take most of the central bank funds for themselves.

The only group that had a judgment in hand was the Havlish group, and it was first in line to begin trying to seize it. If courts ruled that the Afghan bank funds could be used for Taliban debts, the other families might not get anything.

Sean P. Carter is a lawyer for a group of insurance companies. The groups wanted the court to deliver a final judgment in favor of the insurers, which would account for the rest of the Afghan bank assets that Mr. Biden left behind.

Some of the funds from the insurance company would be transferred to the other Sept. 11 groups.

The terms of the potential agreement were not disclosed in the letter to the court. According to Brian Eagleson, a member of the holdout group of plaintiffs, the proposed deal means that the Havlish plaintiffs would keep about $1.75 billion and insurance interests would keep about $500 million.

He said that the other victim groups would get the remaining $1.25 billion. If the court approves the use of the central bank funds for Taliban debts, the potential payouts per estate could be as high as eight-figures, compared with six-figure payouts per estate for the other groups.

Mr. Eagleson's father was killed in the south tower of the World Trade Center.

Mr. Carter didn't say anything. In his letter to the court, he wrote that the proposed deal was the best way to ensure that all Sept. 11 victims get some relief.

Jerry S. Goldman, a lawyer for the group, declined to comment on the substance of the deal or the status of the negotiations. He said he was trying to get the best result for his clients under the circumstances.

A group of victims of a different Qaeda terrorist attack persuaded a judge in New York to issue an order of attachment for the Afghan assets they are bringing a separate lawsuit against.