The eventual exit of a member state from the euro zone is probably inevitable, billionaire investor George Soros has said, but declined to name the country.

"There was no arrangement for any country leaving the euro, which in the current circumstances is probably inevitable," he was quoted as saying at a panel discussion in Vienna.

Soros pointed out that the euro had a basic flaw from the start in that the currency was not backed by political union or a joint treasury.

"The euro had no provision for correction. There was no arrangement for any country leaving the euro, which in the current circumstances is probably inevitable," he said.

While he called survival of the European Union a "vital interest to all", he said the EU needed structural changes to halt a process of disintegration.

According to reports, he also called on the European policymakers to put in place a "plan B" that allows weaker economies to exit the single currency.

"There is no plan B at the moment. That is why the authorities are sticking to the status quo and insisting on preserving the existing arrangements instead of recognising there are fundamental flaws that need to be corrected."

He warned that Europe is on the verge of an economic collapse that would start in Greece, but spread to other countries. According to him, the financial system remains extremely vulnerable.

"Let's face it: we are on the verge of an economic collapse which starts, let's say, in Greece but could easily spread. The financial system remains extremely vulnerable...

"We are on the edge of collapse and that is the time to recognize the need for change."