The Chief Rabbi Lord Jonathan Sacks and Holocaust survivors took part in a candle lighting ceremony on Sunday in Hyde Park to remember the Holocaust.
Survivors and their children and grandchildren lit candles to remember those who were murdered in the Holocaust at the event to mark Yom Hashoah.
The shofar was sounded and a minute's silence was observed.
The Israeli ambassador to the UK Ron Prosor said at the ceremony: "We the Jewish people are a nation of survivors. The state of Israel is a living, breathing monument of our survival. Today there are those who continue to threaten our destruction. Even at the United Nations, president Ahmadinejad shamelessly promotes the evils of Holocaust denial. We can never allow malicious, evil and extreme ideas to remain unchallenged.
"Today as we remember the horrors of the past, we lay down our challenge to those who would attempt to recreate them. Just over a week from now we will celebrate Yom Haatzmaut, and Israel's 62nd anniversary. Our tradition maintains a healthy balance between commemoration and celebration.
"This is a time for remembrance. We remember the past. We face the challenges of the future. We stand united as free people with a thriving state within our ancient homeland, ready, willing and able to defend our freedom."
Video by Jonathan Sacerdoti