The White House has told former national security adviser John Bolton that the draft manuscript of his memoir still contains classified material, his attorney confirmed to The Hill.

The White House plans to provide Bolton with a redacted copy of the draft manuscript by June 19, four days before the planned publishing date, according to Charles Cooper, Bolton’s attorney. The news was first reported by The New York Times.

The Washington Post reported over the weekend that Bolton planned to publish his memoir, “The Room Where it Happened,” on June 23.

The book’s publication has been delayed as a result of a classification review process spearheaded by the White House National Security Council (NSC). The White House told Bolton in January that the manuscript contained “significant amounts of classification” and sought to block certain portions of the book.

In a letter to Cooper this month, White House deputy counsel John Eisenberg warned that the material in the book could pose a national security threat.

“As we advised your client when he signed the nondisclosure agreements, and as he should be well aware as a former assistant to the president for national security affairs in this administration, the unauthorized disclosure of classified information could be exploited by a foreign power, thereby causing significant harm to the national security of the United States,” Eisenberg wrote.

Meanwhile, Bolton has told associates that he believes he has changed the book to satisfy national security concerns raised by the White House and that officials were trying to block the book from public release, according to The New York Times.

Cooper penned an op-ed that ran Wednesday in the Wall Street Journal labeling Eisenberg's letter a "transparent attempt to use national security as a pretext to censor Mr. Bolton, in violation of his constitutional right to speak on matters of the utmost public import." The attorney said the book would be published on June 23, as planned.

Simon & Schuster, the book's publisher, said in a statement Wednesday that Bolton worked with the NSC to incorporate changes that addressed officials' concerns in the months leading up to publication. 

"The final, published version of this book reflects those changes, and Simon & Schuster is fully supportive of Ambassador Bolton’s First Amendment right to tell the story of his time in the Trump White House," the statement read. 

Bolton, who was tapped as Trump’s third national security adviser in March 2018, was ousted from the role in September over disagreements with Trump on a handful of issues.

Bolton’s memoir received a substantial amount of attention at the start of this year when the Times reported that it contained details about the president’s actions toward Ukraine at the center of his impeachment.

The revelations triggered calls for Bolton to be called to testify at the Senate impeachment trial, though the Republican-controlled body eventually voted against calling witnesses and voted to acquit Trump of the charges largely along party lines.

The manuscript reportedly presents a scathing account of business inside the West Wing. Trump earlier this year accused Bolton of writing a “nasty” and “untrue” book.

Updated at 4:14 p.m.