"We are already witnessing an unbearable catastrophe with the fighting in Blue Nile and South Kordofan in Sudan, and the ensuing outpouring of refugees into South Sudan and Ethiopia." Writing from Addis Ababa at the start of an Elders delegation to Sudan and South Sudan, Desmond Tutu blogs for CNN about the region's urgent humanitarian needs and what he hopes the Elders can achieve on their visit.

In the coming days I will be in Juba and Khartoum, the capitals of South Sudan and Sudan.

My fellow Elders Martti Ahtisaari, Mary Robinson and I are going there to try to ensure that the terrible lessons of war are not forgotten – and to share our hope that these two beautiful countries can find a path to peace. We will relay the world's fears of another deadly conflict that would shatter the hopes of both nations and the broader region. And we will tell the leaders that, while it will take time and patience, we believe – as a result of our own experience – that peace can be achieved.

One of our main reasons for going to Sudan and South Sudan now is the humanitarian situation, which must be addressed as a matter of urgency. We are already witnessing an unbearable catastrophe with the fighting in Blue Nile and South Kordofan in Sudan, and the ensuing outpouring of refugees into South Sudan and Ethiopia.

As I write I am in Addis Ababa, Ethiopia, where the African Union is chairing the vital talks between the two countries. The international community is united in its urgent desire to see these talks succeed, with a deadline of August 2 looming very near. This precious window of opportunity cannot be squandered. We will lend our weight and our voice here in any way that we can.

Both Sudan and South Sudan need peace to prosper

I have had the chance to get to know President Salva Kiir well, but this will be my first visit to his country, nearly a year after it became the newest nation on the planet. South Sudan's clamour for independence was such a powerful moment. Now I hope many more achievements await its citizens: gleaming schools, sturdy roads, health facilities and families whose children can look forward to a stable and prosperous future.

But this vision is still distant, and hinges on peace with the North – and within. After the pride of independence, an even greater pride awaits the people when they succeed in building an inclusive government across South Sudan's territory, and across communities and faiths. In Jonglei State, for example, we know of local elders and religious leaders doing much to overcome internal violence. I believe a commitment to dialogue can always overcome unrest, difference and deprivation.

The North faces internal conflicts of its own, as well as with the South. Two other members of The Elders, Lakhdar Brahimi and Jimmy Carter, met President al-Bashir in Khartoum recently, and were pleased to have the opportunity to listen to his perspective. His willingness to discuss the situation with the Elders reinforces our common belief in the vital importance of sustained dialogue.

What can the Elders do?

We believe it is essential to speak to all sides in any dispute. We will listen to President Salva Kiir, who faces the challenge of building a new nation, and to President Omar al-Bashir, who oversees a complex and seemingly intractable situation. We have also listened to the wise counsel of Thabo Mbeki, who chairs the African Union talks between the two countries, and offered our support to his important efforts. We will also meet and listen to some of the victims of this crisis, and give our support to the local organisations who are doing their utmost to build peace from the ground up.

We will be telling them all that reconciliation thrives on dialogue, inclusiveness and forgiveness. Combined, they allow our shared humanity to prevail. I know only too well that it is difficult. But looking back to my own experience in South Africa, I realise we were sometimes blinded by anger and prone to pointing fingers when we should have outstretched our hands. In the end it became clear that it was the people who found the strength to forgive, and to speak to all parties, who were successful in unlocking the situation.

Our final message, on this visit, is that reconciliation, peace and prosperity are the finest legacies a leader can dream of. And we will pray with the people that these leaders shall succeed.