Volkswagen Group’s plan to build a budget car for emerging markets, a key part of its drive to become the world’s biggest automaker, has stalled because the carmaker is struggling to meet cost targets for the vehicle, said Heinz-Jakob Neusser, VW’s brand development chief.Europe’s largest carmaker has been trying for more than a year to hit internal cost requirements for the vehicle, which would likely sell for between 6,000 euros ($8,300) and 8,000 euros and be built in China, the biggest market for budget cars.