The European Central Bank said on Friday it will restrict Greek banks’ access to its cheapest funding operations from Aug 21, a day after the country's bailout program ends.

The ECB will revoke a so-called ‘waiver’ which allowed Greek banks to post junk-rated government bonds as collateral in regular funding operations, in a move that will boost funding costs for Greek lenders.

Such an exemption could only be granted while a country is in a bailout program, and the ECB has long said that the waiver would be revoked, much like in the case of Cyprus in 2016 when it exited its own bailout.