Outspoken on world economic policies and an unapologetic proponent of European integration, Soros has recently called the design of the euro "very flawed" and described the situation as an "existential crisis" for Europe.

FORBES: George Soros

There were also the tensions caused by Germany's reunification and the crises within the European monetary system, which raised the prospect of economic integration going into reverse.

ECONOMIST: Charlemagne

They don't really care about the plight of European leaders at the mercy of an economic crisis that demands one thing: great integration - but could prompt a political crisis demanding the exact opposite: a looser Europe.

BBC: Americans wade in on Euro crisis

His strongest positive proposal is European rather than British: a plea to reverse the Monnet tradition of putting economic before political integration, which he argues has become unsustainable against the horizon of the single currency.

ECONOMIST: British politics