Fiat Chrysler will abandon the use of diesel engines in all its passenger vehicles by 2022, according to a report Sunday.

Demand for diesel versions of passenger cars in Europe is waning and car makers face extraordinarily high costs to get diesel engines to comply with emission limits in real-world use.

FCA is expected to announce the move in a four-year plan for its products and businesses that is to be released on June 1.

DON'T MISS: Cost to make FCA diesels emission-compliant in Europe: half a billion dollars (Jan 2017)

That decision likely stems from a January 2017 statement by CEO Sergio Marchionne that transitioning 80 percent of current diesel engines to new Euro 6 emissions standards would cost the company 500 million euros ($531 million).

The report on the decision emerged on Sunday in the Financial Times (subscription required), the respected British business outlet. Fiat Chrysler declined to comment to the FT on the report.

The company owns the Alfa Romeo, Chrysler, Dodge, Fiat, Jeep, Maserati, and Ram brands.

Sergio Marchionne

Sergio Marchionne

Roughly 40 percent of FCA's vehicle sales in Europe had diesel engines last year, with more than half of those in Italy, where gasoline is expensive and general distaste for diesels has not reached the same heights as in Germany and the U.K.

The move away from diesel threatens to become a trend, with Porsche having announced just last week it had already ended production of its last diesel vehicle and did not anticipate any more.

Similarly, Toyota said it did not plan to develop any further diesel models.

CHECK OUT: Jeep Wrangler Diesel already testing, before 2019 launch (Jul 2017)

The use of the phrase "passenger vehicles," however, leaves considerable wiggle room for FCA's continued use of diesel engines—fitted with the latest urea-based emission aftertreatment systems—in what the U.S. defines as light trucks.

Those include the Ram 1500 full-size pickup truck and Jeep Grand Cherokee sport-utility vehicle, along with the 2018 Jeep Wrangler launched last month at the Detroit auto show.

The first two have been offered with an EcoDiesel 3.0-liter V-6 turbodiesel option that has proven very popular, with one in five Ram 1500 models fitted with it.

2016 Ram 1500 EcoDiesel HFE

2016 Ram 1500 EcoDiesel HFE

FCA has tangled with the EPA on whether those two diesel vehicles contained software that limited or restricted full use of the emission-control system, however.

Nonetheless, it announced that the diesel version of the new Wrangler would go on sale within two years, well ahead of the anticipated plug-in hybrid model of the same vehicle.

Diesel sales have ebbed in Europe amidst years of continuing revelations that they did not meet even the much laxer emission limits required in EU countries until January 1, 2017.

The cost of urea-based emission-control systems to make them compliant threatens to make the cost of diesel versions of smaller European-style hatchbacks too high to sell.

Volkswagen Group has had to modify millions of older diesel vehicles, and a criminal investigation into that company's diesel emission scandal continues in Germany.

For 2018, only BMW, Jaguar, and Chevrolet offer diesel options in the U.S. for passenger sedans, hatchbacks, and wagons.

Volkswagen TDI 'clean diesel' television ad screencap

Volkswagen TDI 'clean diesel' television ad screencap

Diesel engines are widely expected to continue in full-size pickup trucks—Chevrolet, Ford, and Ram have all now announced 3.0-liter turbodiesel options for their full-size pickups—and probably SUVs and crossover utility vehicles as well.

Automakers believe they will let those vehicles meet increasingly stiff U.S. limits on carbon-dioxide emissions and rising corporate average fuel economy requirements at a lower cost than either hybrid or plug-in systems.

Green Car Reports reached out to Fiat Chrysler in the U.S. for any further information; the company declined to comment on the report.