Updated

President Trump said Saturday that he intends to allow the release of long-classified files on the assassination of former President John F. Kennedy, a move that could shed light on a tragedy that has stirred conspiracy theories for decades.

The National Archives has until Oct. 26 to disclose the remaining thousands of never-seen government documents on the 1963 assassination, unless Trump changes course and tries to block their release.

“Subject to the receipt of further information, I will be allowing, as President, the long blocked and classified JFK FILES to be opened,” Trump tweeted Saturday morning.

However, to what additional information the president was referring was unclear.

The CIA and FBI, whose records make up the bulk of the batch, won't say whether they've appealed to the Trump administration to keep them under wraps.

"The American public deserves to know the facts, or at least they deserve to know what the government has kept hidden from them for all these years," Larry Sabato, director of the University of Virginia Center for Politics and author of a book about Kennedy, said in an email to The Associated Press.

It's unlikely the documents contain any big revelations about Kennedy's killing, said Judge John Tunheim, who was chairman of the independent agency in the 1990s that made public many assassination records and decided how long others could remain secret.

Sabato and other JFK scholars believe the trove of files may provide insight into assassin Lee Harvey Oswald's trip to Mexico City weeks before the killing.

During the trip, Oswald visited the Soviet and Cuban embassies.

His stated reason for going was to get visas that would allow him to enter Cuba and the Soviet Union, according to the Warren Commission, the investigative body established by President Lyndon B. Johnson. However, much about the trip remains unknown.

Among the protected information up for release is details about the arrangements the U.S. entered into with the Mexican government that allowed it to have close surveillance of those and other embassies, said Tunheim, a federal judge in Minnesota.

Kennedy experts also hope to see the full report on Oswald's trip to Mexico City from staffers of the House committee that investigated the assassination, said Rex Bradford, president of the Mary Ferrell Foundation, which publishes assassination records.

The White House didn't immediately respond to emails seeking comment.

The FBI declined to comment on whether it has asked Trump to keep the files hidden. A CIA spokeswoman would say only that it "continues to engage in the process to determine the appropriate next steps with respect to any previously-unreleased CIA information."

Congress mandated in 1992 that all assassination documents be released within 25 years, unless the president asserts that doing so would harm intelligence, law enforcement, military operations or foreign relations. The still-secret documents include more than 3,000 that have never been seen by the public and more than 30,000 that have been released previously, but with redactions.

The files that were withheld in full were those the Assassination Records Review Board deemed "not believed relevant," Tunheim said. Its members sought to ensure they weren't hiding any information directly related to Kennedy's assassination, but there may be nuggets of information in the files that they didn't realize was important two decades ago, he said.

"There could be some jewels in there because in our level of knowledge in the 1990s is maybe different from today," Tunheim said.

The National Archives would not say whether any agencies have appealed the release of the documents.

The Archives in July published online more than 440 never-before-seen assassination documents and thousands of others that had been released previously with redactions.

Among those documents was a 1975 internal CIA memo that questioned whether Oswald became motivated to kill Kennedy after reading an AP article in a newspaper that quoted Fidel Castro as saying "U.S. leaders would be in danger if they helped in any attempt to do away with leaders of Cuba."

"Oswald might have had a clear motive, one that we have never really understood for killing Kennedy, because he thought that by killing Kennedy he might be saving the life of Fidel Castro," said Philip Shenon, a former New York Times reporter who has written a book about Kennedy's assassination.

Some of the files will likely remain under wraps, experts say.

It's unlikely the National Archives will release some IRS records, including the tax returns of Jack Ruby, the man who killed Oswald, Bradford said.

Sabato said he also suspects that some key records may also have been destroyed before the 1992 law ordered that all the files be housed in the National Archives.

The Associated Press contributed to this report.