The Federal Reserve Bank of New York has asked the Philippines' central bank to help Bangladesh Bank recover the $81 million that was stolen by hackers in February from its account held at the Fed, boosting Dhaka's efforts to retrieve the money.

In a letter sent on June 23, the New York Fed's General Counsel Thomas Baxter asked Elmore O. Capule, general counsel for the central bank of the Philippines, "to take all appropriate steps in support of Bangladesh Bank's efforts to recover and return its stolen assets."

Almost six months have passed since hackers broke into the Bangladesh central bank's computer systems and sought to transfer away as much as $951 million - eventually managing to steal $81 million in one of the biggest-ever cyber heists. Most of that money is still missing and the culprits have not been identified.