Update | Deadline moved to Sunday after Greek leader Tsipras unveils 'vague' debt plan at last-ditch euro zone summit

When the emergency euro-zone summit opened in Brussels at 2am this morning (Hong Kong time), all eyes were on the proposals Greek Prime Minister Alexis Tsipras would bring to the table as his country's banks face potential meltdown.

With Greek lenders down to their last few days of cash and the European Central Bank tightening the noose on funding, Tsipras had to persuade the bloc's other 18 leaders, many of whom are exasperated with five years of crisis, to open negotiations fast on a new loan to rescue Greece.

However, Tsipras failed to present them with a detailed plan. Overcoming their surprise, the leaders reluctantly agreed to a final summit on Sunday, saying that could give both sides an opportunity to stave off collapse of the struggling but defiant member nation. European leaders were angry and frustrated, according to diplomatic sources.

Underscoring the gravity of the challenge, European Union President Donald Tusk decided to call all 28 EU leaders to Brussels instead of only the 19 euro zone members, because, for the bloc, it “is maybe the most critical moment in our history”. 

And highlighting the rising anger with Tsipras over months of foot-dragging and surprising negotiating twists, European Commission President Jean-Claude Juncker had a stark warning for Greece.

“We have a Grexit scenario, prepared in detail,” he said, referring to the situation in which Greece would have to exit the currency union.