Hungarian born billionaire George Soros has warned the EU faces a collapse akin to the Soviet Union unless major changes are forthcoming.

Citing the spasms of upheaval in Italy, Britain and Germany, he said that Europe had drastically underestimated the threat from its “internal enemies” and was on the cusp of tipping into “the nightmare of the 21st century”.

In an article for Project Syndicate, a Prague-based website, he said that the rise of anti-EU populism before the European elections at the end of May could once again throw the continent into violent chaos. Nationalist parties are expected to win a substantial number of seats in France, Italy, Sweden, Germany and Poland, and may emerge as one of the most powerful forces in the next European parliament.

“Neither our leaders nor ordinary citizens seem to understand that we are experiencing a revolutionary moment,” Mr Soros wrote. “Most of us assume that the future will more or less resemble the present but this is not necessarily so. In a long and eventful life I have witnessed many periods of what I call radical disequilibrium. We are living in such a period today.”