Our global mission takes many forms -- from development to peacekeeping, to human rights and good governance. Today, however, I would like to concentrate on two issues. The first is the one that I broached in my address to this year's General Assembly. It is a controversial issue, but I believe that one of my responsibilities as Secretary-General is to highlight major issues that the international community needs to confront, even when, perhaps especially when, they are controversial and difficult.

My objective was to stimulate a vigorous debate among Member States on what I consider one of the most important and difficult challenges facing us as we move into the new millennium.

How do we ensure that the United Nations plays its rightful, effective role in maintaining international peace and security?

Our role in the area of peace and security has evolved significantly over the last decade. Many of the new peacekeeping missions deployed over this period involved the United Nations in situations of internal conflict, where we sought to put an end to senseless bloodshed and often massive violations of human rights. But, as this year's Kosovo crisis showed us, there is as yet no consensus within the international community about its rights and responsibilities in such circumstances.

There is often a tension between the cardinal principle of sovereignty and the equally fundamental value of human rights, both enshrined in the United Nations Charter. In recent years, there have been interventions in compelling humanitarian situations or where there have been gross and systematic violations of human rights. Our own Charter makes it clear that "armed force shall not be used, save in the common interest".

But what is the common interest?

In my speech to the General Assembly in October, I invited Member States to consider this vital question.

Who defines it?

Who acts to defend it; under whose authority?

Clearly, the Security Council is the only body with the international responsibility to take such action.

But in the past, on Rwanda, it has been united in inaction, and on Kosovo, it was disunited. The North Atlantic Treaty Organization (NATO) took action outside the Council's authority.

We must do better than this.

A new consensus must be developed so that the Council acts in defence of our common humanity. I welcome the debate that has begun among Member States on these issues.

The second issue I would like to discuss with you is the idea of the "Dialogue among Civilizations". As many of you know, this is an idea that is being advanced by the recently-elected President of Iran, Mr. Khatami, and the General Assembly has elected to make the year 2001 the Year of the Dialogue among Civilizations. This dialogue is based on a belief that global diversity is a precious asset and that we all can learn from the beliefs and the ways of life of other peoples and other cultures.

Tolerance of those who are different -- of their views, their cultures, their beliefs and their ways of life -- is a hallmark of all great civilizations and is essential for a world such as our own, in which people of many different cultures are striving to coexist peacefully. The United Nations' struggle for tolerance is based on the belief that it is diversity which gives humanity its promise. No union of nations, no assembly of people and no community can thrive without tolerance. Without that basic respect between human beings, man is doomed to a bitter fate, and the United Nations -- as an idea and a reality -- will never fulfil its destiny.

The battle for tolerance and against intolerance still needs to be fought. Without question, the conflicts of the post-cold-war world -- from Rwanda to the Balkans to Indonesia -- were all rooted in the absence of tolerance and the demonization of particular groups or ethnicities.

Solely on the grounds of ethnic belonging, innocent and defenceless men, women and children have been persecuted and exterminated. They are the ultimate victims of intolerance. The United Nations University will shortly release a major study which examines the role of "horizontal inequities" -- that is inequities between groups in a society -- in generating tension and conflict. While these disparities alone may not lead to war, they can be exploited by elites seeking to provoke conflicts.

By its decision to dedicate the year 2001 to a "Dialogue among Civilizations", the General Assembly has placed the United Nations at the centre of the process of mutual understanding and cooperation that I believe will help secure a peaceful, prosperous and tolerant twenty-first century. There is a growing global understanding of the meaning and promise of dialogue and communication.

Indeed, I believe that history should teach us that, alongside a global diversity of cultures, there exists one worldwide civilization of knowledge within which ideas and philosophies meet and develop peacefully and productively. This is the civilization for which the United Nations labours every day in every part of the world; it is the civilization which recognizes that true progress is based on lasting peace and prosperity; the civilization within which clashes of ideas take place peacefully and productively.

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