Diplomatic sources said a Saturday session addressed prospects for future African political integration and a charter for African democracy, main themes of the weekend meeting in Banjul, capital of the west African state of Gambia.

The proposed charter would ban attempts to change member-states' constitutions so as to extend the terms in office of African presidents.

But the sources said the project had been postponed because of the strong opposition of some presidents attending here.

Predicting that outcome recently, South African Foreign Minister Nkosazana Dlamini-Zuma publicly deplored the refusal of certain countries to adopt what he said wouud be a charter that would complicate efforts by unpopular presidents to remain in power.

Addressing the summit Saturday, United Nations Secretary-General Kofi Annann expressed concern to his fellow Africans at conflicts still raging on the continent and at suppression of press freedom in some African countries.

"The conflicts in Darfur, Ivory Coast, Somalia and northern Uganda continue to outrun efforts for a solution," he said.

On Saturday, a top AU official told the more than 50 African leaders they must pay more urgent attention to crises in Sudan and elsewhere.

"We are being summoned urgently to look at the crises in Sudan, Darfur and Somalia," said Alpha Oumar Konare, chairman of the AU commission.

In Somalia, Konare said, African leaders had to act firmly to encourage dialogue between the two sides in the lawless country.

"We need an integrated African force in order to tackle these conflicts," he said.

The AU is pulling out its poorly-equipped force from Darfur by September to open the way for UN peacekeepers, though the Sudanese government is opposed to an international peacekeeping force.

The United Nations is conducting the largest humanitarian operation in the world in Darfur, an area roughly the size of France where up to 300,000 people have been killed and 2.4 million displaced by three years of civil war.

Konare and current AU chairman Denis Sassou Nguesso of the Republic of Congo both expressed concern at the deteriorating situation in Somalia.

"The rescue of Somalia lies in indispensable dialogue and necessary compromise," said Sassou Nguesso, urging fellow-leaders to support transition institutions struggling to assert their authority.

Guest speakers here on Saturday included President Hugo Chavez of Venezuela and Iran's hardline President Mahmoud Ahmadinejad.

Chavez called on Africa to join with Latin America in "south-south" cooperation, especially in oil and banking to escape from what he called foreign domination.

Ahmadinejad said global "bullies" were annoyed at the technological advancement of smaller developing countries.

"People see that the bullies of the world get angry because of the technical and scientific advancement of other countries and they wish to keep the countries and nations backward," he said.