The journalist Glenn Greenwald said on Thursday that he was leaving The Intercept, the news website he helped found, claiming that it had refused to publish an article he wrote on Joseph R. Biden Jr. unless he removed sections that were critical of the Democratic presidential nominee.
Mr. Greenwald, who is best known for his role in making public the National Security Agency documents leaked by Edward Snowden in 2013, said in a statement that he would continue to publish his work at Substack, a digital platform for subscription newsletters.
He announced his decision to leave The Intercept in a Substack post, writing that the “final, precipitating cause” was that “The Intercept’s editors, in violation of my contractual right of editorial freedom, censored an article I wrote this week, refusing to publish it unless I remove all sections critical of Democratic presidential candidate Joe Biden, the candidate vehemently supported by all New-York-based Intercept editors involved in this effort at suppression.”
In his resignation post, Mr. Greenwald referred to “the Hunter Biden materials,” suggesting that the disputed article was about digital data taken from a laptop computer said to belong to the candidate’s son.
Betsy Reed, the editor in chief of The Intercept, disputed Mr. Greenwald’s claim that he had been censored.
“Glenn Greenwald’s decision to resign from The Intercept stems from a fundamental disagreement over the role of editors in the production of journalism and the nature of censorship,” she wrote in a statement.
Ms. Reed added that his post about his departure was “teeming with distortions and inaccuracies — all of them designed to make him appear a victim, rather than a grown person throwing a tantrum.”
The statement included some qualified praise.
“We have the greatest respect for the journalist Glenn Greenwald used to be, and we remain proud of much of the work we did with him over the past six years,” the editor wrote. “It is Glenn who has strayed from his original journalistic roots, not the Intercept.”
In a phone interview, Mr. Greenwald said he had received a “story memo” from The Intercept outlining what the publication would allow and not allow in his article. “My arrangement with The Intercept since it began is my opinion pieces are not edited by anyone,” he said.
The Intercept was founded in 2013 by Mr. Greenwald, the filmmaker Laura Poitras and Jeremy Scahill, with backing from the eBay billionaire Pierre Omidyar.
In his Substack post, Mr. Greenwald wrote that he had been considering starting his own media outlet before making the decision to leave The Intercept. In the interview, he said he had talked with “journalists who kind of are politically homeless, who are neither fully entrenched in the liberal left media or the Democratic Party, nor the pro-Trump right.”
For now, Mr. Greenwald will be part of a growing number of journalists who have left major media outlets to try their luck at Substack. The group includes Andrew Sullivan, formerly of New York Magazine, and Matt Taibbi, formerly of Rolling Stone.