President Joe Biden has like his predecessors held off on releasing secret documents related to the assassination of John F. Kennedy, angering some members of the former president's

family. Some of the records — which had been set for release on Tuesday based on a deadline set in 2018 by former President Donald Trump (who released some but delayed other documents during

his own term) — are now scheduled to be made public on Dec. 15, according to a White House memo that also directs agencies to undergo an "intensive 1-year review" for remaining

records with a second release now scheduled for Dec. 22, 2022. The National Archives and Records Administration, led by U.S. Archivist David Ferriero, says more time is needed for various

orderly process; not decisions or releases made in haste." But two nephews of President Kennedy, who was shot and killed in Dallas on Nov. 23, 1963, objected to the additional delays.

"They should just release the records. It's been 58 years," Robert F. Kennedy Jr. tells PEOPLE. "Are they trying to seriously tell us they haven't had time to read

them? ... And the White House is saying they haven't had time to read them in three generations. It just makes people think that government lies, and it makes Joe Biden look like a

liar. He's doing the same thing Trump did: He promised to release them and now he's saying no, the same as Trump." Robert's cousin Patrick Kennedy likewise told

_Politico_ that "he wants transparency when it comes to the assassination — an event he said "that left such a scar in this nation's soul that lost not only a president but a

promise of a brighter future." "I think for the good of the country, everything has to be put out there so there's greater understanding of our history," Patrick said.

Says Robert: "Of course there are questions that everybody would like to see answered. We don't know what's in the files." "I think the question that many Americans

are asking today is: Who are they protecting? It's been 58 years," Robert says. "What secret is so important would be so damaging to our government that they need to keep it

locked up for 60 years?" The President John F. Kennedy Assassination Records Collection Act of 1992, which became law when Biden was a U.S. senator, states that government records

concerning the death of JFK "should be eventually disclosed to enable the public to become fully informed about the history surrounding the assassination." But the law allows for

delays "when postponement remains necessary to protect against an identifiable harm to the military defense, intelligence operations, law enforcement, or the conduct of foreign

relations that is of such gravity that it outweighs the public interest in disclosure." In the nearly 60 years since the assassination, "the profound national tragedy of President

Kennedy's assassination continues to resonate in American history and in the memories of so many Americans who were alive on that terrible day," Biden said in the White House memo

on Friday. "Meanwhile, the need to protect records concerning the assassination has only grown weaker with the passage of time," he continued then. "It is therefore critical

to ensure that the United States Government maximizes transparency, disclosing all information in records concerning the assassination, except when the strongest possible reasons counsel

otherwise." The memo also instructs Ferriero's agency to come up with a plan by Dec. 15 of this year to "digitize and make available online" more than 250,000 previously

disclosed records and to add context about the records. * WITH REPORTING BY ADAM CARLSON