ISTANBUL (Reuters) -A senior Iranian official said on Saturday that proposals put forward by European powers at talks in Geneva about his country's nuclear programme were "unrealistic", suggesting that if they stuck to them it would be difficult to reach an accord. There were few signs of progress on Friday after the foreign ministers of Britain, France and Germany, known as the E3, plus the EU met their Iranian counterpart in a bid to prevent the conflict between Israel and Iran from escalating.