(CNN) - Caitlyn Jenner is taking back her support for President Trump.
The former Olympic athlete turned transgender activist wrote about her change of views in a Washington Post opinion column published Thursday.
She said she thought Trump would help trans people but was wrong.
Jenner also said in the column that "the trans community is being relentlessly attacked by this president."
Her comments come after The New York Times reported that the Trump administration is considering a proposal to narrowly define sex.
If adopted, that definition could exclude transgender people from existing civil rights protections in education, employment and access to health care.
Activists spoke out against the report, saying at a march outside the White House on Monday and in a trending social media hashtag that they "won't be erased."
"The leader of our nation has shown no regard for an already marginalized and struggling community. He has ignored our humanity. He has insulted our dignity," Jenner wrote in The Post.
She added Trump has "made trans people into political pawns as he whips up animus against us."
"This is politics at its worst," she wrote. "It is unacceptable, it is upsetting, and it has deeply, personally hurt me."