We must turn the greatest collective challenge facing humankind today – climate change – into the greatest opportunity for common progress towards a sustainable future.

You are already leaders. Your ideas, your actions and your decisions make a difference. More than any other generation, you have a voice. Social networking is changing how we interact - and it can change our world. You are in touch with peers from around the world. You understand the power of instant communication. I appeal to you to use that power for the common good, the power of communication and the power of networking.

I spend most of my time in South Korea but at least one-third of my time is spent traveling around the world, meeting people, speaking about climate change and sustainable development and trying to foster global citizenship especially for young people. What I observe is there clearly is a need for global citizenship. That is exactly right. We are having troubles around the world. We need global vision.

The future of any leader or political systems is to be determined by the people of the country.

With her courage and determination, Malala has shown what terrorists fear most: a girl with a book.

We must unite. Violence against women cannot be tolerated, in any form, in any context, in any circumstance, by any political leader or by any government.

Today, we have more than 110,000 men and women deployed in conflict zones around the world. They come from nearly 120 countries ... Thanks to their efforts, life-saving humanitarian assistance can be delivered and economic development can begin.