CNN  —  Uri Berliner, a National Public Radio senior editor who wrote a scathing online essay accusing the public radio network of harboring a liberal bias, said Wednesday he had resigned from the outlet. “I am resigning from NPR, a great American institution where I have worked for 25 years,” Berliner wrote in a resignation letter to NPR chief executive Katherine Maher, which he posted to his X account. An NPR spokesperson declined to comment. Berliner’s resignation came after he was suspended for five days without pay over his 3,500-word piece in the anti-establishment publication The Free Press. In the essay, Berliner claimed NPR had failed to properly cover allegations Donald Trump colluded with Russia in the runup to the 2016 election, the controversial Covid-19 lab-leak theory and New York Post’s story on Hunter Biden’s laptop. Berliner used his complaints about how those individual stories were covered by his colleagues to draw a sweeping conclusion that NPR had lost “viewpoint diversity,” and started “telling listeners how to think.” NPR editor-in-chief Edith Chapin quickly pushed back against Berliner’s characterization of the outlet, telling staff in a memo that network management “strongly disagree with Uri’s assessment of the quality of our journalism and the integrity of our newsroom processes.” “We believe that inclusion — among our staff, with our sourcing, and in our overall coverage — is critical to telling the nuanced stories of this country and our world,” she added. Other NPR staffers publicly rejected Berliner’s assessment in social media posts. In his resignation letter, Berliner said he did not support calls to defund NPR and that he wants to see the audio-focused outlet thrive. But he said he could not “work in a newsroom where I am disparaged by a new CEO whose divisive views confirm the very problems at NPR I cite in my Free Press.” Berliner was referencing a number of old tweets uncovered in recent days by right-wing activists in which Maher posted disparagingly about Trump. Isabel Lara, an NPR spokesperson, dismissed the attacks, saying Maher “was not working in journalism at the time and was exercising her First Amendment right to express herself like any other American citizen.”