"I don't anticipate that the ESM will be able to disburse the first subtranche before the second half of March," Regling said at a press conference.
In January, the finance ministers of the eurozone countries agreed on a new 6.7-billion euros tranche of financial aid for Greece.
The payment will be split in two parts, and the first one, amounting to 5.7 billion, was originally expected to be disbursed in late February.
Previous year, the European Stability Mechanism agreed to disburse 7.7 billion euros to help Greece meet its July obligations.
Regling said earlier that after disbursing the tranche, ESM would have over a half of the Greek public deb, making the European Stability Mechanism with European Financial Stability Facility (EFSF) the largest creditor of Greece.