Extinction Rebellion's co-founder, Roger Hallam, has caused outrage after telling a German publication that the Holocaust was "just another f***ery in human history".
In an interview with Die Zeit, the 53-year-old appeared to downplay the genocide of six million Jews by Nazi Germany and claimed Germans' attitude towards the massacre was holding them back.
He said: "The extremity of a trauma can create a paralysis in actually learning the lessons from it.
"The fact of the matter is, millions of people have been killed in vicious circumstances on a regular basis throughout history".
Hallam mentioned other mass killings during the last 500 years, including the Belgians' slaughter in the Congo, adding: "They went to the Congo in the late 19th century and decimated it."
He suggested that because other genocides had repeatedly taken place over the centuries, the Holocaust could be considered "almost a normal event".
His comments have been heavily criticised, with Germany's foreign minister, Heiko Mass, among those condemning them.
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In a post on Twitter, he said: "The Holocaust is more than millions dead and cruel torture methods.
"To assassinate and destroy Jews industrially is uniquely inhumane. We always have to be aware of that, to make sure: never again!"
Extinction Rebellion's German branch has condemned Mr Hallam's comments and said he was "no longer welcome" in Germany.
In a post on Twitter, it said: "We explicitly distant ourselves from Roger Hallam's belittling and relativising statements about the Holocaust.
"In so doing he contravenes the principles of XR, which does not tolerate antisemitism, and he is no longer welcome in XR Germany."
Extinction Rebellion UK has also "unreservedly" denounced Hallam's comments.
In a statement, the group said: "Jewish people and many others are deeply wounded by the comments today.
"Internal conversations have begun with the XR Conflict team about how to manage the conflict process that will address this issue.
"We stand by restorative outcomes as preferable, although in some cases exclusion is necessary.
"Our 6th Principle states: 'We welcome everyone and every part of everyone working actively to create safer and more accessible spaces'. Our movement must be safe for Jews as well as all other minorities, marginalised peoples, and religious groupsRead More – Source