A new documentary entitled “Unacknowledged” claims to reveal years of cover-ups within the US government over the alleged truth of alien visitations of Earth being kept hidden from the public.

Directed by Michael Mazzola and following conspiracy theorist Dr Steven Greer, who is a major player in the so-called “disclosure movement,” the film calls for an end to an alleged truth embargo which ensures the cover up continues.

The extensive documentary touches on the death of Marilyn Monroe, which it suggests was a murder coordinated by the CIA because of an alleged affair with President John F Kennedy.

Dr Greer has produced an alleged top secret CIA memo written two days before the star was found dead on August 5th 1962 in Brentwood, Los Angeles, California.

He claims it shows how she was wire tapped by the agency which had concerns about her liaison with the president.

The alleged memo suggests JFK told her he had seen evidence of “things from outer space” at a secret air base and officials panicked that she may disclose this at a press conference.

Dr Greer claims the memo was referring to the remains of the alleged infamous Roswell UFO crash said to have landed in the New Mexico desert in July 1947.

On his website, Dr Greer states: “We have a number of smoking gun documents, including a wiretap of Marilyn Monroe the day [sic] before she died, which has never been declassified.

She was threatening to hold a press conference to tell the world what Jack Kennedy had told her during pillow talk about having seen debris from an extraterrestrial vehicle at what the document calls a ‘secret air base’.

She was murdered for this.”

Dr Greer is well respected among some UFO circles, but has been branded a hoaxer by more sceptical investigators, something he vehemently denies.

However, he has been behind some extraordinary claims in the past, including stating that the US government has obtained technology from aliens that could provide the world with free energy, but suppresses it to ensure the fossil fuel industry can thrive.

He also claims to be able to summon UFOs and that he once did this in conjunction with the French Ministry of Defence.

The French ministry declined to comment on his claims.

Jonathan Liu, CIA spokesman, rubbished claims of the confidential memo.

He said: “Such claims are baseless and do not merit serious consideration.”

The documentary suggests that there have been many sightings of UFOs, but that they have been covered up by the government for various reasons.

Dr Greer believes that the government is withholding information about extraterrestrial life because of the potential impact it could have on the world.

He stated: “The secrecy around this subject has enabled those in power to control our perception of reality and keep us as a species preoccupied with meaningless issues.”

The documentary does not just focus on conspiracy theories; it also highlights some of the evidence that supports the existence of extraterrestrial life.

It includes interviews with whistleblowers who claim to have worked in secret government projects, as well as with astronauts and military personnel who have witnessed strange phenomena.

Dr Greer hopes that the documentary will spark debate about the subject and encourage people to push for more transparency from the government.

He said: “I hope that this film will be a wake-up call for people to demand that their governments come clean about what they know.

We need to move beyond a belief system that has been created to control us and start exploring the universe with an open mind.”