The remaining U.S. government records on the 1963 assassination of President John F. Kennedy, which shocked the United States and the world and gave rise to numerous theories and speculations, were released Tuesday by the Trump administration.

The move follows an executive order signed by President Donald Trump in January, ordering the release of the remaining records on the assassinations of JFK, as well as his brother Robert F. Kennedy and civil rights leader Martin Luther King.

"All documents withheld for classification reasons" on the assassination of President Kennedy are being made public, the United States National Archives announced in a statement.

Millions of pages of documents relating to this major event in American history have already been published over the past few decades.

Thousands more had been banned from publication by the CIA and FBI, citing national security reasons.

The Warren Commission, which investigated the assassination of the charismatic 46-year-old Democratic president, concluded that it was carried out by a former Marine sniper, Lee Harvey Oswald, acting alone.

But this official conclusion did little to quell speculation that a more sinister plot was behind the assassination of President Kennedy in Dallas, Texas.

And the state's slow release of case files has fueled various conspiracy theories.

Many experts believe it is unlikely that the documents still in the Archives' possession will contain groundbreaking revelations or put an end to the pervasive conspiracy theories surrounding the assassination of the 35th president of the United States.

Lee Harvey Oswald was shot dead by strip club owner Jack Ruby on November 24, 1963, two days after Kennedy's assassination, while being transported to prison.

Until now, much of the material already released has contained purely factual material, including dozens of reports from FBI agents who followed leads that led nowhere.

Much of this information was already known, such as the fact that the CIA, then obsessed with communism, had hatched several ludicrous plots to assassinate Cuban leader Fidel Castro.

Lee Harvey Oswald defected to the Soviet Union in 1959, before returning to the United States in 1962.

Like Oliver Stone's 1991 film "JFK," hundreds of productions and writings have fueled conspiracy theories, pointing the finger at the Soviet Union, Cuba, the Mafia, and even Kennedy's Vice President, Lyndon Johnson.

The release of the documents is part of a law passed by Congress in 1992 requiring that documents relating to the assassination held in the National Archives be fully released to the public 25 years later.