Fifty years ago this week, on the eve of the historic Apollo 11 launch, world leaders were invited by NASA to send messages to the Moon.

However, based on records at the British National Archives, it appears that the British royals were not enthusiastic about the endeavor right away.

According to The Guardian, Queen Elizabeth's then-private secretary wrote that the text of a message was written and approved, but he made clear the queen was not in love with the idea: “Her Majesty agrees that this idea is a gimmick and it is not the sort of thing she much enjoys doing but she certainly would not wish to appear churlish by refusing an invitation which is so obviously well intentioned.”

Queen Elizabeth's message to the Moon, as seen at the British National Archives. (British National Archives)

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The queen's initial reaction is shown by the National Archives in a forthcoming blog post celebrating the 50th anniversary of the Apollo 11 launch.

Her message was sent on a tiny disc carried by astronauts Neil Armstrong and Buzz Aldrin. It reportedly read: "On behalf of the British people, I salute the skills and courage which have brought man to the moon. May this endeavour increase the knowledge and well-bring of mankind."

In this July 20, 1969 photo made available by NASA, astronaut Buzz Aldrin, lunar module pilot, walks on the surface of the moon during the Apollo 11 extravehicular activity. (Neil Armstrong/NASA via AP)

The royal's message was just one of 73 sent from figureheads and leaders of countries worldwide.

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The National Archives show will include a range of documents and artifacts from that era.

The archives reportedly include an apology from then-U.K. ambassador to the United States, John Freeman, for missing the historic Apollo 11 launch. The Guardian reports that he admitted his absence was a “mistake,” but explained that having witnessed the launch of Apollo 10 at Cape Kennedy just two months previously, “a further visit so soon afterwards would be a pure pleasure jaunt.”

In this July 20, 1969 image made from television, Apollo 11 astronaut Neil Armstrong steps onto the surface of the moon.  (NASA via AP)

In addition, four tiny pieces of Moon dust, which were gifted to Great Britain by President Richard Nixon, can also be seen at the exhibit.