The bombing of the United Nations' headquarters in Iraq - killing at least 17 people, including the UN special representative for Iraq, Sergio Vieira de Mello - has provoked worldwide condemnation.
The UN has vowed to continue its work in Iraq despite the blast
Here is some of the reaction from around the world.
UN Secretary General Kofi Annan
We will continue our work... We will persevere, we have work to do. We will not be intimidated.
Pope John Paul II
The tragic news that reaches us from Baghdad and Jerusalem
in the past hours can only make us feel deep sadness and
Mary Robinson, former UN human rights chief and predecessor of Sergio Vieira de Mello
This may be a wake-up call for the world that the situation in Iraq wasn't very tenable before this terrible outrage... It's an appalling blow and the world must rally.
US President George W Bush
The civilised world will not be intimidated, and these killers will not determine the future of Iraq. Iraq is on an irreversible course towards self-government and
French President Jacques Chirac
Such hateful acts arouse nothing but indignation and the strongest condemnation.
German Chancellor Gerhard Schroeder
It is an attack on the international community of states, but also an attack on the future of the Iraqi people.
UK Foreign Secretary Jack Straw
The UN had quite consciously eschewed the idea that they should be part of a secure area precisely to emphasis their separateness and independence of the US-UK coalition forces.
Russian Foreign Minister Igor Ivanov
The fact that terrorists targeted the United Nations, which spares no effort in helping the Iraqi people overcome the war's consequences and return to normal life, is particularly outrageous.
Chinese President Hu Jintao
The process of Iraq moving towards independence and
steady development will not be stopped and the UN mission will not be suspended either.
Egyptian Foreign Minister Ahmed Maher
Egypt condemns such an act which targeted individuals
performing their national duty with all sincerity, and
Syrian foreign ministry quoted by the official news agency
This condemned criminal act should not influence the UN's role in helping the Iraqi people restore their freedom and
Australian Foreign Minister Alexander Downer
What was the UN doing in Iraq? It was providing food,
it was providing shelter, it was providing humanitarian
assistance. A terrorist... has gone and attacked the
people who were in Iraq to help.
Brazil's President Luiz Inacio Lula da Silva
[Brazilian Sergio Vieira de Mello] was a victim of the insanity of terrorism.