German authorities at the Federal Office of Motor Vehicles (KBA) had previously said that they couldn't rule out the EA288 also being designed to fool regulators' tests.
VW says that since this September it has only been selling vehicles fitted with a new version of the engine which complies with tougher Euro-6 regulations.
Until Thursday it had always insisted that the “current diesel motor generation EA288 was not affected” by the scandal.
Germany's biggest carmaker admitted around a month ago that millions of its vehicles were fitted with software designed to reduce the engine's emissions of harmful Nox gases when it detected it was being submitted to standardized tests.
The cheating engines were built into roughly 11 million vehicles worldwide, including 8.5 million in the European Union and 2.4 million in Germany itself.
Earlier this week, new VW boss Matthias Müller had assured workers at the Wolfsburg headquarters that the scandal would not affect them personally.
“At the moment we have no reason to think of shortening working hours” as a way to cut labour costs, Müller said.
The company board says that the emissions scandal has so far not impacted sales.