It seems like ages since Mazda introduced the new 2.2-liter four-cylinder diesel engine in the European market. The company has stated several times in the past that they haven't ruled out bringing a diesel to America, while at the same time watching their words and not casting unfounded hope for one. Instead, Mazda claims that it's always watching the market and if there was a demand for a diesel, it would look at offering it.
Mazda also has a more powerful 2.3-liter diesel which would be better suited for the United States. Mazda already offers the CX-7 with an SCR system that would go a long way to meeting American emissions standards. However, at the last Tokyo Motor Show, the company also showed a next-generation diesel which is 20 percent more efficient. Looks like we'll have to see when the diesel option will become part of the U.S. lineup.