Greenpeace activists protest with a banner reading: "Your diesel cartel makes us sick" in front of the Federal Transportation Ministry in Berlin, Germany, Wednesday, Aug. 2, 2017. German auto bosses, ministers and state governors are considering how to reduce diesel emissions as drivers face the threat of possible bans on driving older diesel cars in some cities. A meeting Wednesday is to bring together leading politicians with bosses from Volkswagen, Porsche, Audi, Mercedes, BMW, Opel and Ford. (Kay Nietfeld/dpa via AP)

German automakers committed Wednesday to fitting over 5 million diesel cars in the country with updated software to reduce harmful emissions and to finance incentives for drivers to trade in older models, the transport minister said.

Wednesday's "diesel summit" brought together leading ministers and state governors with bosses from Volkswagen, Porsche, Audi, Mercedes, BMW, Opel and Ford. It came amid worries about possible bans on driving older diesel cars in some cities and wider questions over whether diesel as a technology even has a future.

Transport Minister Alexander Dobrindt said the automakers will fit some 5.3 million diesel cars with new software, starting "in the coming months." The VDA auto industry group said that applies to most diesel cars of types made since 2009. It said the aim is to reduce nitrogen oxide emissions by 25-30 percent, and the overall figure includes 2.5 vehicles already being refitted by Volkswagen.

The automakers also agreed to come up with self-financed incentives to encourage drivers to get older vehicles off the road faster, Dobrindt said.

BMW said it would give owners of older diesels registered before 2009 an "environment bonus" of up to 2,000 euros ($2,360) if they trade in their older car for a new electric or hybrid model, or for a lower-emissions internal combustion car meeting current standards.

Police officers control the back entrance of the German Interior Ministry where a meeting of leading politicians with bosses from German car makers take place after the meeting at its original planed location, the Transport Ministry, was canceled, in Berlin, Wednesday, Aug. 2, 2017. German auto bosses, ministers and state governors are considering how to reduce diesel emissions as drivers face the threat of possible bans on driving older diesel cars in some cities. A meeting Wednesday is to bring together leading politicians with bosses from Volkswagen, Porsche, Audi, Mercedes, BMW, Opel and Ford. (AP Photo/Markus Schreiber)

The auto industry also is to contribute an unspecified amount to a German government "sustainable mobility fund" for cities aimed at using technology to make traffic flow better.

Dobrindt said the government will invest some 250 million euros ($295 million) more in modernizing city public transport fleets such as buses and taxis.

Volkswagen has been under intense scrutiny since admitting nearly two years ago that it equipped vehicles with software that manipulated emissions levels. German automakers have been under additional pressure in recent weeks following a report that the biggest companies colluded for years over diesel technology and other issues.

The brand logo of German car maker BMW is photographed on a car in Berlin, Tuesday, Aug. 1, 2017. German Transport Minister Alexander Dobrindt and Environment Minister Barbara Hendricks call the heads of German car makers for a meeting named National Diesel Forum to Berlin on Wednesday, Aug. 3, 2017. (AP Photo/Markus Schreiber)

German Environment Minister Barbara Hendricks criticized VDA's statement on measures offered at the summit, saying the was tone "was marked too little by insight and humility."

Even before Wednesday's meeting, industry critics and some officials had called for wider-ranging refits going beyond software updates. Industry representatives indicated that wasn't realistic, said Stephan Weil, the governor of Lower Saxony state, although the topic will be examined further by experts.

"The automakers have got their way again," said Herbert Behrens, a lawmaker with the opposition Left Party. "They are getting a cheap version to keep selling dirty diesels."

  • The brand logo of German car maker Volkswagen, VW, is photographed on a car in Berlin, Tuesday, Aug. 1, 2017. German Transport Minister Alexander Dobrindt and Environment Minister Barbara Hendricks call the heads of German car makers for a meeting named National Diesel Forum to Berlin on Wednesday, Aug. 3, 2017. (AP Photo/Markus Schreiber)

  • The brand logo of German car maker Mercedes Benz is photographed on a car in Berlin, Tuesday, Aug. 1, 2017. German Transport Minister Alexander Dobrindt and Environment Minister Barbara Hendricks call the heads of German car makers for a meeting named National Diesel Forum to Berlin on Wednesday, Aug. 3, 2017. (AP Photo/Markus Schreiber)

  • The brand logo of German car maker Audi is photographed on a car in Berlin, Tuesday, Aug. 1, 2017. German Transport Minister Alexander Dobrindt and Environment Minister Barbara Hendricks call the heads of German car makers for a meeting named National Diesel Forum to Berlin on Wednesday, Aug. 3, 2017. (AP Photo/Markus Schreiber)

  • The brand logo of German car maker Mercedes Benz is photographed on a car in Berlin, Tuesday, Aug. 1, 2017. German Transport Minister Alexander Dobrindt and Environment Minister Barbara Hendricks call the heads of German car makers for a meeting named National Diesel Forum to Berlin on Wednesday, Aug. 3, 2017. (AP Photo/Markus Schreiber)

  • The brand logo of German car maker Porsche is photographed on a car in Berlin, Tuesday, Aug. 1, 2017. German Transport Minister Alexander Dobrindt and Environment Minister Barbara Hendricks call the heads of German car makers for a meeting named National Diesel Forum to Berlin on Wednesday, Aug. 3, 2017. (AP Photo/Markus Schreiber)