It’s been three years since VW admitted to having cheated during diesel emissions tests, something that eventually turned out to be one of the most expensive scandals in automotive history.

Now however, the automaker is more than ready to let bygones be bygones, with CEO Herbert Diess claiming that his company has put “most” of the scandal in the past, due in part to VW’s electric vehicle strategy, but also a massive $30 billion investment aimed to make things right.

“We basically bought back and fixed close to 90 percent of the cars globally,” stated Diess in an interview. “I think most of the things we have overcome. We still have legal issues worldwide, in Germany – you are aware of that – and it will take years to solve everything. We just settled with Audi [in late October], with the state attorneys in Germany. There are still legal issues, but technically, we overcame most of the issues.”

Yet, VW’s legal issues in Germany have not been as serious as what’s been going on in the U.S. where the automaker pleaded guilty to three felonies: conspiracy, obstruction of justice and introducing imported merchandise into the U.S. with false statements, as reported by Automotive News Europe.

“The fix in Europe was relatively easy, it was a software update for about 10 million cars,” added the VW CEO, before saying that the situation in the U.S. was “by far the most critical one worldwide. And it has to do with the emission regulation here in the United States, which is much tougher than in the rest of the world.”

The former BMW exec also claims that diesel still has a future in VW’s portfolio, as it is considered a more “rational” powertrain choice in certain cases, such as for long distances and larger vehicles.

VW will continue to make diesel-powered vehicles, “because in many countries, you don’t have renewable energy available,” concluded Diess. “And then, if you make the counts, diesel is probably still the best option for low CO2-emission mobility.”