Europe's largest truckmakers have committed to phasing out diesel trucks by 2040, a decade earlier than originally planned, the Financial Times reported this week.

Seven manufacturers—Daimler, Scania, MAN, Volvo, DAF, IVECO, and Ford—signed an agreement to transition to zero-emission vehicles under the auspices of the ACEA auto-industry trade group, according to the report.

European regulators have discussed curtailing sales of gasoline and diesel passenger vehicles, and have introduced stricter emissions standards to encourage sales of electric cars, but less attention has been paid to commercial vehicles. The United Kingdom, for example, plans to ban sales of new internal-combustion cars by 2035, but hasn't done the same for diesel trucks.

That major manufacturers are willing to phase out diesel powertrains from commercial trucks in Europe indicates that diesel's days are numbered.

Daimler Trucks North America Portland factory

Until recently, diesel dominated the European market—in both passenger cars and commercial vehicles. Large commercial trucks are among the last vehicles to use diesel engines by default, so the fact that manufacturers are willing to discuss a phase-out timeline is significant.

In the United States, reducing diesel emissions is complicated by the proliferation of heavy-duty pickup trucks. These are considered commercial vehicles under Environmental Protection Agency regulations, but are often used for personal transportation. Emissions tampering on these pickups is rampant, and that could be polluting more than the vehicles affected by the Volkswagen diesel scandal, a recent report found.

At the same time, a contingent of 15 states plans to require most new commercial trucks sold within their jurisdictions to be electric by 2050. California, however, plans to achieve that goal five years earlier—in 2045.

Daimler—which builds sells and manufactures trucks in both Europe and the U.S.—has also committed to carbon-neutral manufacturing. The company announced on Monday that its Portland, Oregon, factory had achieved carbon-neutral status, with the other factories slated to follow by 2025.