David Cameron has refused to back calls for a minute's silence during the Olympics' opening ceremony to commemorate 11 athletes murdered in a terror attack at the Munich Games 40 years ago.
The Prime Minister said it was important to remember what happened in 1972, but that planned memorial events were the proper way to do that.
His comments came after the widows of two Israeli athletes who were killed in the attack pleaded with the International Olympic Committee (IOC) to allow a minute's silence during Friday's opening ceremony.
Ankie Spitzer and Ilana Romano, whose husbands Andrei Spitzer and Yosef Romano were among 11 athletes killed in the attack at the Olympic Village in Germany, handed a petition to IOC chiefs yesterday containing more than 105,000 signatures from people around the world backing the call for a silence.
"I think that what matters is we properly commemorate this," Mr Cameron said.
"I myself will be going to the Guildhall commemorative event."
London Mayor Boris Johnson had attended a similar event in Hackney, north London, and another had been held in the London 2012 athletes' village, he added.
"It's very important that we remember what happened in '72, and the loss of life and the appalling actions that were taken," he said.
"I think those things are the right way to commemorate it but I add my voice, as it were, to the need to commemorate properly, but I think that has been carried out."
Mr Cameron added: "It's right that in 2012 - 40 years on from the Munich Olympics - we remember the Israeli team members who were killed there.
"We will be properly marking the anniversary of that tragedy with a special commemoration and every day of these Games we'll be demonstrating that there is no more diverse, more open, more tolerant city in the world than this one."