Greece could crash out of the eurozone as early as this summer if Britons vote to leave the European Union in the upcoming referendum, economists have predicted.

The uncertainty following a 'yes' vote to Britain leaving the EU would put unsustainable pressure on Greece’s cash-strapped economy at a time when it is also struggling to cope with an influx of migrants escaping turmoil in the Middle East and Africa, according to a report from the Economist Intelligence Unit.

The authors of the report say it is highly likely that Greece will be forced to leave the eurozone at some point within the next five years, but that if the UK votes to leave the EU in June, it could happen much sooner.

Greece is already under a huge amount of pressure and a so-called Brexit could tip it over the edge. The country has large debt payments due in mid-2016, while structural reforms recommended in Greece's bail-out programme are “slow burners” and unlikely to deliver any significant growth in the short term.

Greece's true GDP contracted by 0.3pc last year, while unemployment stands at 24pc. The country's overall debt-to-GDP ratio has hit 171pc.

"While the region could probably handle a Brexit, Grexit or an escalation of the migrant crisis individually, it would be unlikely to navigate successfully a situation in which several of those crises came to a head simultaneously," the report, entitled 'Europe stretched to the limit', said.