The drumbeat for cleaner cars is only getting stronger.

Last week President Donald Trump announced that his administration would extend the review period for the EPA's 2022-2025 fuel economy guidelines by about a year, causing concern over a backslide in vehicle emissions. However, some industry analysts believe cleaner tailpipes are all but inevitable, despite Trump's ruling.Industry experts concede the Trump administration will likely delay the adoption of more stringent tailpipe regulations, but a total rollback is seen as doubtful. "I don't think we're going to see a rollback," Kristin Dziczek, director of the Center for Automotive Research's labor and industry group, told Reuters. "At most, I think we may see a slowing of the timetable."

Although the Trump administration might soften emission rules in the U.S., more stringent requirements are being put into place in Europe and China, so further development will be need regardless. And if the U.S. remains a step or two behind those global standards, automakers could choose to invest their money elsewhere.

It also remains to be seen how much weight EPA requirements actually carry. The rapid development of green technology could ultimately render EPA requirements a moot point. Moreover, buyers have come to expect better fuel economy from newer vehicles (even with low gas prices), so consumer sentiment might have a greater sway over automakers.

Fuel economy standards that cover 2022-2025 are expected to be completed by April 2018.