On Monday, the National Green Tribunal (NGT) asked the Delhi transport authorities to immediately deregister all diesel vehicles, that are more than 10 years old following complaints that a lack of enforcement of judicial orders was hurting the Capital’s fight against pollution.

The order came after complaints of non-implementation of NGT’s order of April 2015, wherein it had banned diesel vehicles that were over 10 years old from plying on the roads of Delhi and the National Capital Region (NCR).

But despite the orders, older cars continued to ply on Delhi’s roads with the city government saying only the regional transport office (RTO) had the authority to ban old vehicles.

The tribunal’s chairperson, Justice Swatanter Kumar, ordered the RTOs of the Transport Department that after de-registration, it should issue a public notice and submit the list of such vehicles to the Delhi Traffic Police.

Older cars are more harmful for the environment as they have primitive pollution control systems installed and emit more harmful gases than their newer variants. Vehicular exhaust comprises a big chunk of the air pollution that chokes Delhi.

So, to improve the city’s air that is among the worst in the world, this is the latest step in a raft of judicial measures.

As per the traffic police "repeated challans and fine on offending older vehicles hadn’t fetched any result.

According to a study by IIT Kanpur, diesel vehicles contribute 78% of particulate matter – tiny particles that can penetrate the lungs – comes from four-wheelers.