The meeting comes as Greece gears up for its referendum Sunday and on the fifth day of restrictions on banking transactions, with Greeks limited to 60 euro daily withdrawal limits.
Many ATMs have run out of 20 euro notes, meaning the limit for many has effectively been reduced to 50 euros.
The official, who spoke only on condition of anonymity in line with government rules, did not reveal what was being discussed.
And Greek police say dozens of anti-establishment protesters have raided a supermarket in an Athens suburb and handed out food to people.
The incident happened in the Vyronas area, in the east of the capital, when about 30 protesters entered the supermarket, took food off the shelves and scattered pamphlets in and around the store.
Police say no one was hurt.