President Donald Trump announced in a social media post on Thursday that he has directed the Department of Commerce to begin work on a new US census that excludes undocumented immigrants from the population count.

States with large undocumented populations like California and Texas would see their political power diminished if people in the U.S. illegally were omitted from the official population count.

The direction comes amid Trump's push to weaken the political power of those voters less likely to support him.