Fredrik Erixon, who was voted one of the most influential economists in Europe, has warned Angela Merkel and her Brussels gang cannot stop the end of the European project.
Speaking at an economic conference, the Oxford graduate declared that "the era of an ever-closer union has ended".
The economist, who has advised the British government in the past, said the hope the election of Emmanuel Macron brought to the EU was misguided.
Leading EU figures such as Mr Juncker and Mrs Merkel has suggested that the French presidential result means that the European project will only get stronger.
The idea of an ever-closer integration union is ended – according to this expert economist
Sorry Juncker! The Brussels economist claims the idea of a growing, vibrant EU is over
However, Mr Erixon said: "Despite the victories of the Dutch Prime Minister and Emmanuel Macron, as much as I like to share their positive view about European cooperation and empowering the EU with more authority, I think the era of an ever-closer union has ended.
"The notion of the ever-closer union has been very, very strong for more than 60 years, but it has died.
"It didn’t end with Brexit nor did it end with Trump’s scepticism about the EU.
"It ended far earlier than that – 15 years ago when France and the Netherlands voted against the constitutional treaty.
"This was an early warning about declining support for anything that suggested a deeper integration."
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Erixon said the idea of the EU was in decline
The notion of the ever-closer union has been very very strong for more than 60 years, but it has died
The economist said the economic growth was poor in the EU and getting worse.
He explained: "The economic growth premium of European integration has also weakened.
"This was a core selling point for a long time.
"It was a promise there if you join the EU, you’re going to be better off, your economy will become better with deeper integration.
"Economic growth is not just poor at an EU level, but across individual level too, across all countries.
"In 1990s, at least some countries were growing at a high level – but now it is poor everywhere."
Despite Juncker and Macron's hope, the European project may be on the way out
The Swedish economist, who lives in Brussels, warned that the EU will not be able to resolve tensions around the "major problems of our time" – migration and unemployment.
Mr Erizon, who founded the European Centre for International Political Economy, said Europe will soon be reduced to a mere transaction-based union.
He continued: "The EU has moved into a political culture that is purely transactional.
"We will see much less of the visionary generosity that guided the EU in the past, in the expansion of the EU to Eastern countries.
"The ambitious political culture of the European project has died."