As for a replacement? Good question...

Fiat Chrysler Automobiles will end production of its diesel vehicles by 2022, telling the Financial Times a lack of demand and high costs are behind the decision.

According to the report, people "familiar with the [diesel] strategy" say the company will announce decision as part of a four-year plan, set to be fully revealed on June 1.

Fiat Chrysler has been accused of using 'defeat devices' to circumvent emissions regulations. Last year, the US Government accused the company of using dodgy software on 104,000 Ram 1500 and Jeep Grand Cherokees fitted with the 3.0-litre EcoDiesel engine.

Although it initially planned to "vigorously defend" itself and outright denied "any deliberate scheme to install defeat devices" on its cars., should it accept a settlement offer from the US Department of Justice (DoJ), FCA is facing fines and a major recall.

US DoJ Lawyers reportedly argued the settlement needed to include "very substantial civil penalties" to deter other manufacturers from fitting defeat devices on their cars, and said the punishment needs to “adequately reflect the seriousness of the conduct that led to these violations".

This news is the latest addition to a growing list of setback for diesel-powered vehicles. Last week, Porsche confirmed production of the Macan S diesel and Panamera 4S diesel had ended, and there's no word on when the diesel Cayenne will be arriving, if at all.

A report in the The New York Times, published in January, alleged a research group funded by BMW, Bosch, Daimler and Volkswagen tested emissions on live monkeys, in an attempt to prove newer diesel vehicles are safer than the soot-blowing vehicles of yesteryear.

Although the initial reporting was vague, and CarAdvice hasn't seen the documents cited in the original article, Volkswagen has since asked for "forgiveness for this bad behaviour". It has also suspended its lobbying head over the issue.

It's unclear how Fiat Chrysler intends to replace diesel in its lineup. Sergio Marchionne, FCA CEO, is noted for his dislike of electric vehicles and, unlike most of its rivals, the organisation hasn't outlined a concrete plan for its electrified future.

The most recent Ram 1500 will be offered with a hybrid powertrain, potentially hinting at the direction the brand will take.

Expect more details when the four-year plan is revealed on June 1.