The Trump administration has decided to delay the release of some classified documents on John F. Kennedy’s assassination, citing national security reasons.

Despite his promise last year to release all files related to the investigation into JFK’s assassination, President Trump announced in a White House memo on Thursday that some documents would be withheld for review until October 2021.

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“The continued withholdings are necessary to protect against identifiable harm to national security, law enforcement, or foreign affairs that is of such gravity that it outweighs the public interest in immediate disclosure”, said President Trump said in the memo.

#JFKFiles pic.twitter.com/AnPBSJFh3J

— Donald J. Trump (@realDonaldTrump) October 28, 2017

The president had given the CIA, FBI and other agencies until April 24 to release the secret documents related to President Kennedy’s assassination by Lee Harvey Oswald in Dallas. on Nov. 22, 1963.

President Trump did authorize the release of 19,045 documents, which are now available on the National Archives website.

President John F. Kennedy.

President John F. Kennedy.

In October 1992, President George H.W. Bush signed the John F. Kennedy Assassination Records Collection Act, requiring that all assassination documents “shall be publicly disclosed in full and available” at the National Archives “no later than the date that is 25 years after the date of the enactment of this act.” The law allowed for postponements if the government was worried that harm to security “outweighs the public interest in disclosure.”

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More than 2,800 documents on the assassination were published in October 2017, and the National Archives made an additional four releases in November and December for a total of 35,000 documents released last year. Many of these documents had redactions.

It is unclear how many documents are being kept secret under the new directive. Although the remaining files are set to be revealed by October 2021, it is possible their release could be postponed again by national security agencies.

H/T Independent, The Washington Post, Los Angeles Times, History.com

John F Kennedy and Jackie in the motorcade on November 22, 1963.