Volkswagen to retrofit 4 million diesel vehicles

Carmaker Volkswagen has offered to retrofit an additional 1.5 million diesel vehicles on Thursday, less than a week before the German government holds a "Diesel summit" with automotive industry representatives.

The announcement came as the firm received Barbara Henricks (SPD), the Minister for the Environment, at its flagship Wolfsburg plant. Previously, Volkswagen had agreed to retrofit 2.5 million vehicles in the wake of the "dieselgate" scandal.

Volkswagen AG was the first German carmaker which was revealed to have installed illegal software which falsified emissions test results for its diesel vehicles in 2015.

A U.S. federal judge ruled in April 2017 that Volkswagen "must pay a... 2.8 billion (dollar) criminal fine for rigging diesel-powered vehicles to cheat on government emissions tests."

"We are aware of our responsibility for the environment and jobs." Chief Executive Officer Matthias Mueller said on Thursday in a statement. Volkswagen wanted to make a contribution to the success of the upcoming "Diesel Summit."

For Hendricks, the German automotive industry faces significant changes.

"This is a turning point," she said ahead of her meeting in Wolfsburg with Mueller.

Hendricks admitted that close ties between German politics and car manufactures in the past had created an negative impression of excessive comradery between the two.

"I cannot completely reject those accusations," Hendricks said. As a result, it was necessary to improve government supervision of the industry.

Despite the planned modification measures announced by several German carmakers, the Minister for the Environment still thought that outright bans on diesel vehicles remained a possibility.

These would become necessary if regulatory thresholds for nitrogen oxide pollution were continuously breached, even though such measures were a final resort.

Together with the Transport Minister Alexander Dobrindt (CSU), Hendricks will meet with German carmakers at the "Diesel summit" to discuss software upgrades, as well as technical improvements to motors in order to reduce nitrogen oxide emissions.

Recent allegations of illicit collusion in the German automotive industry were not part of the summit's agenda, although they would undoubtedly affect the "atmosphere of the debate", according to Hendricks.