Vermont Sen. Bernie Sanders called on President-elect Donald Trump to rescind his offer for Stephen Bannon to serve a key role in his administration.

“This country, since its inception, has struggled to overcome discrimination of all forms: racism, sexism, xenophobia and homophobia. Over the years we have made progress in becoming a less discriminatory and more tolerant society — and we are not going backward,” Sanders said in a statement Wednesday. “The appointment by President-elect Trump of a racist individual like Mr. Bannon to a position of authority is totally unacceptable.”

“In a democratic society we can disagree all we want over issues, but racism and bigotry cannot be part of any public policy. The appointment of Mr. Bannon by Mr. Trump must be rescinded,” the Vermont senator continued.

Sanders is not the only one who is critical of Trump’s promotion of Bannon to chief strategist on Monday.

Critics say that Breitbart News, the website Bannon headed until he left to join Trump’s campaign, has racist and anti-Semitic content.

But Trump’s aides have pushed back.

Reince Priebus, who Trump named as his chief of staff, said the criticism of Bannon did not reflect the person he knew.

"I find him not to be the way that’ he’s being accused, I find him to be the opposite,” Priebus said.