"We are considering public transport free of charge in order to reduce the number of private cars," Environment Minister Barbara Hendricks, Finance Minister Peter Altmaier and Agriculture Minister Christian Schmidt wrote in a letter to EU Environment Commissioner Karmenu Vella seen by AFP Monday.
"Effectively fighting air pollution without any further unnecessary delays is of the highest priority for Germany," the ministers added.
A deadline arrived on January 30 for Germany and eight fellow EU members including Spain, France and Italy to meet EU limits on nitrogen dioxide and fine particles or face legal action.
Brussels environment chief Vella gave countries extra time to present further pollution-busting measures.
Alongside free transport, the politicians promised new laws by year's end to limit emissions from buses, cabs and other fleet operators, updated traffic regulations and low emission zones, further tax breaks for less-polluting vehicles and technical retrofits to existing motors.
German ministers promised to work with state and local governments on the schemes, which will be tested in the cities of Bonn, Essen, Herrenberg, Reutlingen and Mannheim.
But Association of German Cities chief Helmut Dedy warned that "we expect a clear statement about how (free transport) will be financed" from the federal government.
"This can't be implemented in a hurry," agreed Michael Ebling, head of the German Association of Local Utilities.
Air quality has surged to the top of Berlin's priorities over the past year.
Environmentalists brought court cases aimed at banning diesel cars from parts of some city centres.
Fears millions of diesel drivers could be affected prompted Chancellor Angela Merkel to promise action and squeeze carmakers for funding, in the wake of successive diesel emissions cheating scandals.
"Life-threatening" pollution affects more than 130 cities in Europe, according to the Commission, causing some 400,000 deaths and costing 20 billion euros ($24.7 billion) in health spending per year in the bloc.
Countries that fail to keep to EU limits could face legal action at the European Court of Justice, the EU's highest tribunal, which can levy fines on the member states.
The Commission has already targeted Bulgaria and Poland with lawsuits.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)