Professor Hari Tsoukas of Warwick Business school, who is currently in Athens writes: “It is rather irresponsible of Tsipras to call for a referendum. First, it is unconstitutional. The Greek constitution explicitly prohibits a referendum on fiscal matters. Secondly, it is technically extremely difficult for a referendum to be organised in five days and for people to be properly informed. Thirdly, the referendum is on a technical document that has been withdrawn and on a programme that expires tonight. Strictly speaking, the referendum lacks substance.

“Why is Tsipras doing it? Partly because he does not have the courage to take a painful decision that will split his party, preferring to pass the ball to the people; partly because he has been trapped by his own increasingly hardening anti-bailout rhetoric; and partly because he intends to use the referendum as a negotiating ploy.

“He thinks that a ‘no’ vote will enable him to come back stronger to the negotiating table. However, this has been clearly ruled out by creditors. Tsipras has chosen to put his party over and above the country. He is gambling the future of his country. Instead of being a strong leader who will do what it takes to keep the country in the euro zone, he has chosen to be a weak leader who would rather be dragged along by the hardliners of his party.

“Having said this, he has been pushed to this by the creditors’s intransigent demands that perpetuate the excruciating austerity that has been imposed on Greece. The moment of truth for Greece and for the euro zone approaches. The looming calamity will have been brought by both parties refusing to see the big picture and seek a compromise.”