BERLIN - Iran and six world powers have made progress in talks in Lausanne, Switzerland, about Tehran's nuclear program and a deal is possible, but not yet certain, a German foreign ministry spokeswoman said on Wednesday. 'There is progress to be seen, an agreement is possible but nothing is yet certain,' said the spokeswoman at a regular government news conference in Berlin. 'An agreement must stop Iran's path to a nuclear bomb in a verifiable, long-term and credible way,' she said adding there would not be a 'bad deal'.