ISRAELI ambassador Daniel Taub hosted a commemoration ceremony for the athletes murdered during the 1972 Munich Olympic Games.
The occasion was marked despite the International Olympic Committee's refusal to hold an official minute's silence during the games.
It had held a sombre ceremony earlier last week, with Lord Coe and Mayor of London Boris Johnson in attendance - though it did not have the exposure an official occasion would have.
The ceremony was simulcast across Jewish communities, including in Manchester, where the Jewish Representative Council staged a memorial at the Jewish Museum.
Ambassador Taub told the crowd in London: "We are gathering here, together with thousands of people joining us through the internet, to remember the Olympics' darkest moment.
"The murder in Munich of the 11 Israeli athletes was a tragedy for Israel and the Jewish people.
"Just decades after the Shoah, we witnessed the murder of Jews as Jews on German soil."
He added that the ideology that drove the terrorists of 1972 to murder Jews, continues to compel Israel's modern enemies.
"It was a tragedy that we need to remember especially when once again terrorism has raised its head in Bulgaria," the London-born diplomat explained.
"But it was also, very directly, an attack on the Olympic spirit.
"The hostage taking of Olympic athletes, in the Olympic village, during the Olympic Games was a direct assault on the Olympic ideal of peace and understanding through friendship, solidarity and fair play.
"And that is why it needs to be remembered publicly as a message that those ideals have not been forgotten.
"That is why we are here, why we remember, why we will never forget."
Conservative MP Bob Blackman, in attendance, described the IOC's "snub" as a "great shame on the Olympic movement".
He also announced that on September 5, Parliament would hold a 90-minute debate on the issue.
The memorial included a prayer to remember the fallen and the lighting of candles.
Zionist Federation director Alan Aziz, who organised the commemorations alongside the Embassy, explained: "We must not let people forget.
"This groundswell of support has demonstrated that people understand the importance of remembering it and the innocent victims of that fateful day."