Controls slammed on Greek banks

ATM withdrawal caps of €60 (A$87) will continue for banks in Greece until after this Sunday's referendum, and the country's bank branches themselves are now "closed".

Sunday's referendum question asks: "Greek people are hereby asked to decide whether they accept a draft agreement document submitted by the European Commission, the European Central Bank and the International Monetary Fund, at the Eurogroup meeting held on June 25."

Accepting the agreement would mean implementing an austerity plan demanded by the IMF and the rest of the Eurozone that would result in pension cuts and steep tax increases.

Post-vote scenarios range from staying inside the single European currency, to a return to the drachma.

If Greece's citizens vote in the negative and reject the agreement, the chances of an exit from the Euro are higher.

The Greek government decided on Sunday night that it had no option but to close the nation's banks the following day, after the European Central Bank raised the stakes by freezing the liquidity lifeline that has kept them afloat during a six-month run on deposits. The Athens Stock Exchange did not reopen on Monday either. The country is expected to default on its IMF loans later today.

Early polling suggests Greek prime minister Alexis Tsipras, who has said he wants a 'no' vote, faces defeat by voters who overwhelmingly want to remain in the Eurozone, despite ongoing protests against austerity.