Five important questions about the Greek debt talks

What would the effects be of a Grexit and is it the worst scenario for the eurozone?

Why is a Greek deal so urgent?
In theory, Athens has until 30 June - when it is due to make a a1.6bn (1.15bn) payment to the International Monetary Fund - to secure a fresh injection of cash from its creditors. They have held up the a7.2bn remaining in its bailout fund, until an agreement on economic reforms can be reached.

But it has become increasingly clear that the country's already fragile financial sector is now suffering a debilitating bank run. A total of a2bn was withdrawn from Greek banks between Monday and Wednesday this week, as scared savers opt to put their cash under the mattress. That more than swallows up the a1.1bn increase in emergency funding for Greek banks that the European Central Bank rubberstamped on Wednesday.

Related: Greek crisis: EU leaders to hold crisis summit after talks fail - live updates

Related: Why Greece might now have the upper hand in crunch talks