Until earlier this year Otmar Issing advised Germany's Chancellor Angela Merkel, and he remains one of Europe's most influential economic voices.
When the Euro was being planned he believed that political union was essential but now he fears that centralising power and sharing financial risk could provoke a public backlash. He tells Hardtalk's Shaun Ley there is no public demand for political union.
You can watch the full interview on BBC World News on Monday 1st October 2012 at 03:30, 08:30, 15:30 and 20:30 GMT. It also broadcasts on the BBC News Channel in the UK at 04:30 BST on Monday 1st September and 00:30 BST on Tuesday 2nd October 2012.
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