At the scene: Joe Miller, BBC News, Athens
Throughout the ups and downs of the recent negotiations, Greeks have by and large resisted the urge to withdraw money from their accounts, pinning their hopes on a last minute deal with the country's creditors.
But as the deadline for Greece's 1.6bn payment to the IMF looms, and with Mr Tsipras calling for a referendum next week, lines have begun to form outside ATMs and bank branches in Athens.
One bank has imposed withdrawal limits of 3,000 per account, and some ATMs have handwritten "empty" signs on them - although I managed to withdraw cash at two separate locations.
Some customers were given a ticket number and told to come back in a few hours. One man told me he was 170th in line. "The game is over," said Peter, one of those queuing. "Greece is going into uncharted waters, and the banks will be closed on Monday, I suspect."
Anxiety is mounting in Athens. "Everybody's really scared," Elena, a woman in her 20s, tells me as she waits to withdraw cash. "We need to have enough money to last the week."
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Mr Varoufakis told reporters that the Eurogroup's refusal to extend the bailout could permanently damage the credibility of the group
BBC news