Sources say talks between U.S. president Barack Obama and Chinese president Hu Jintao aimed at reducing tensions over claims of currency manipulation didn’t go as well as expected and that a deal between the two economic behemoths is unlikely. Meanwhile, other G20 leaders have voiced their concern about an impeding currency war between China and the U.S. Earlier on in the summit, British prime minister David Cameron said G20 leaders must address the issue of competitive currency devaluations in order for the global economy to grow and to be shielded against another financial crisis. “We need to deal with this idea that export success for one country is a disaster for other countries. Trade isn’t a zero-sum game,” said Cameron.