Manhattan District Attorney Alvin Bragg on Wednesday issued a warning to Simon & Schuster about an upcoming tell-all book written by a prosecutor who quit the office’s investigation into former President Donald Trump.

“Mr. Pomerantz is under an obligation to receive prior written permission from the DA’s Office before making any disclosures relating to the ‘existence, nature, or content’ of any communications or records or documents that relate in any manner” to the probe, reads a letter sent to the publishing house by Bragg’s general counsel Leslie Dubeck.

Bragg is worried that former prosecutor Mark Pomerantz’s book, “People v. Donald Trump: An Inside Account,” could prejudice his ongoing criminal investigation into Trump, according to Dubeck’s letter, obtained by The Post.

The missive, also addressed to Pomerantz, warned him “not to take any further stops that damage an ongoing criminal investigation.”

Pomerantz, a former federal prosecutor in Manhattan and criminal defense attorney, was brought on in 2021 by then-DA Cy Vance to join the investigation.

He served as the special council assistant district attorney until he abruptly quit in February 2022, along with another lead investigator, Carey Dunne, over disagreements with Bragg on how to proceed with the investigation.

Last week, after the sentencing of the Trump Organization in a tax fraud case, Bragg said his team would “move on to the next chapter” of its investigation,.

On Tuesday, former Trump attorney and fixer Michael Cohen told The Post he met with members of Bragg’s investigative team digging into the ex-president’s finances. He was asked questions about the hush money given to adult film actress Stormy Daniels.

“We stand behind Mark Pomerantz and his book, People vs. Donald Trump, and look forward to sharing this important and timely work with readers when it is published on February 7,” said a spokesperson for Simon & Schuster in a statement.

Pomerantz did not return a request for comment.