Between 11 and 22 July 1995, a militia of Bosnian Serbs carried out a genocide of more than 8,000 Bosniaks in the village of Srebrenica, in what is now eastern Bosnia and Herzegovina.
The massacre took place during the Bosnian War, one of the series of conflicts in the Balkans that followed the collapse of Yugoslavia.
The 25th anniversary of the genocide has been marked across the globe this week.
During and after the Balkan Wars, thousands of refugees fled the region, including many who settled in Luxembourg.
The full text of Bettel's speech can be read below.
'There are celebrations we would prefer not to have to celebrate. We thought that 50 years after we discovered Auschwitz, Birkenau, Dachau, we never would have again something like that on our continent.
That's what we all said and believed. And we discovered 50 years later, 25 years ago, what happened in Srebrenica. 8,000 people died in a week. Why? Why? We still have no answer to all the questions. We even don't have the names of all the people who killed or have been killed there. Not yet. 25 years later, still some family members are missing.
I hoped that we learnt from the Second World War, but realise that still politicians on our continent, two hours flight from my country, did what we said would never happen again on our continent. Deciding to kill others because they were different: ethnicity, religions, political opinions, sexual orientations.
And we realise that still today, in some countries, not that far away from here, some politicians try to divide us, try to be popular by blaming others. We should never forget what happened 25 years ago.'
