One reason why it's almost impossible for Italy to become the next country to leave the EU

A little-known article of the Italian constitution means that it is highly unlikely that Italy will be the next country to leave the European Union - an event that would have the potential to cause chaos across Europe.

Writing in a research note discussing the likely outcomes and impacts of the country's upcoming referendum on constitutional reforms, Morgan Stanley staff members Daniele Antonucci and Phanikiran Naraparaju point to Article 75 of Italy's written constitution, which enshrines the fact that Italy cannot hold a referendum on anything related to international treaties.

Here is the pertinent passage of the constitution (emphasis ours):

"A general referendum may be held to repeal, in whole or in part, a law or a measure having the force of law, when so requested by five hundred thousand voters or five Regional Councils. No referendum may be held on a law regulating taxes, the budget, amnesty or pardon, or a law ratifying an international treaty."

Membership of both the European Union and the euro, are by definition international in nature, and as a result, for Italy to give its people a say on leaving either, the constitution would have to be changed. Obviously, that is no easy task and would require a strongly eurosceptic government with a serious will to leave the EU.

This is the chain of events Naraparaju and Antonucci think needs to happen for Italy to drop out of the EU (emphasis ours):

"So, the bar for leaving is high and the chain of events much longer than, say, for the UK to leave the EU. In Italy, a eurosceptic party would have to win an election with an absolute majority and then set in motion the exit process after having changed the constitution with a two-thirds majority in both chambers or 'just' an absolute majority followed by a referendum. As eurozone membership is indissolubly linked to EU membership, leaving the EU would also automatically mean leaving the EMU."

Fears that Italy's upcoming constitutional referendum, which is also seen as a referendum on Matteo Renzi's premiership, could trigger the country's exit from the EU have been expressed by many. In August, Nobel Prize-winning economist Joseph Stiglitz told Business Insider that the referendum could lead to a "disastrous outcome" and a "cataclysmic event" in Europe.

However, while the populist Five Star Party is gaining support, it seems unlikely that it will be in the position to win a two-thirds majority any time soon, making it virtually impossible that Italy will leave the EU.

Renzi suggested on Monday that he may not stay on if the referendum does not pass. Previously he has indicated that he would remain in government if he lost the vote.

Asked in a radio interview what he would do if the "no" vote won in the referendum, he said: "If I have to stay on in parliament and do what everyone else has done before me, that is, to scrape by and just float there, that does not suit me," according to Reuters.