(7 Jan 2016) The top executive of the Volkswagen (VW) brand worldwide said on Wednesday he was optimistic that US environmental regulators would approve fixes within the coming weeks or months for diesel engines that cheat on emissions tests. Herbert Diess, Volkswagen's chief executive of passenger vehicles, said at the Consumer Electronics Show (CES) in Las Vegas that the company is holding "close dialogue" with American environmental regulators. But the US Environmental Protection Agency (EPA) was not as optimistic, issuing a statement on Wednesday saying that talks with VW so far had "not produced an acceptable way forward." VW has admitted cheating by installing software in its popular 2.0-litre diesel engines that illegally turns emissions controls on during government tests and turns them off on real roads. Nearly 600,000 cars are affected in the US, with a total of 11-million worldwide. US fixes will likely include complicated recalls and take several years for some of the older models. When asked if he envisaged any criminal prosecutions of German VW workers, Diess said the company would focus on their customers before "thinking about the legal background". VW first acknowledged in September that the cheating software was included in its diesel cars and Sport Utility Vehicles sold since the 2009 model year, as well as some recent diesel models sold by the VW-owned Audi and Porsche brands. You can license this story through AP Archive: http://www.aparchive.com/metadata/youtube/fb460266cc52727018fa80e3cf81205e Find out more about AP Archive: http://www.aparchive.com/HowWeWork