A person familiar with the “resolution and assistance” agreement told Reuters the New York Fed would prepare affidavits and clear employees to testify at hearings or a trial, and also allow Bangladesh Bank representatives to interview employees on relevant and factual matters.

The deal could provide some relief to Bangladesh’s central bank and sets the stage for its long-promised litigation over the February 2016 cyber heist, one of the world’s biggest. Since then, it has recovered only about $15 million of its money.

Hackers pulled it off by breaching Bangladesh’s systems and using the SWIFT global payments network to send fraudulent orders to the New York Fed, which oversees the account. Of nearly $1 billion requested, $81 million was sent to accounts at Manila-based bank RCBC and then mostly vanished into Philippines casinos.

In the US District Court in Manhattan on Thursday, Bangladesh Bank sued Rizal Commercial Banking Corp and accused it and dozens of others, including several top executives, of involvement in a “massive” and “intricately planned” multiyear conspiracy to steal its money.

RCBC did not respond to a request for comment on the lawsuit. But on Wednesday, before it was filed, the bank said: “We welcome this complaint, as it is an opportunity for RCBC to put on record again that it was a victim of what was started in Bangladesh by still unnamed persons.”

A 2016 Reuters investigation into the heist found that a series of missteps and miscommunications between the Fed and Bangladesh, little emergency backup, and slow reactions in New York to early warning signs all contributed.

Under the agreement struck this week, the New York branch of the US central bank would provide relevant non-privileged documents and information to Bangladesh Bank or to the court, and serve as consulting or testifying expert, according to the person familiar with it.

It also commits the New York Fed and Bangladesh Bank to “meeting jointly with the relevant agencies or parties in the Philippines to strongly encourage them to assist in the recovery of stolen funds,” the joint statement said, adding the fraud “represents a threat to the international funds transfer system.”

Some 250 foreign central banks and governments keep more than $3 trillion of their assets at the New York Fed.