Volkswagen CEO Martin Winterkorn has apologised for the car giant using software to cheat emissions tests. It comes after US regulators ordered almost half a million cars to be recalled, after they had a device which lowered nitrogen oxide emissions, but only during testing. Winterkorn said he was “personally” sorry that the trust of customers had broken, and that an external investigation of the matter had been ordered. The U.S. Environmental Protection Agency said Volkswagen could face fines of up to $18 billion (AED 66 billion).