HAMBURG (Reuters) – Volkswagen’s (VOWG_p.DE) fixes for diesel vehicles in Europe are running smoothly, a spokesman said after the company said its fixes in North America may cost 2.5 billion euros ($3 billion) more than expected.

“We have to work more on the hardware,” he said. “Customers have to wait longer for their vehicles to be repaired.”

“Here in Europe, it’s all going smoothly,” he added.

In Europe, regulators have allowed Volkswagen to address its diesel-emissions problems with software fixes for the 8.5 million vehicles affected.

In the United States, where the diesel test-cheating scandal originated, the carmaker must also provide hardware fixes and in some cases buy back cars.