NAIROBI, Kenya – Sudanese leaders signed a peace deal that, if implemented, will end Africa’s longest-running conflict and transform politics in a nation that has spent 40 of the last 50 years at war with itself.

Turning the incredibly detailed agreement into reality, though, may prove more difficult than the eight years of talks required to draft it.

The vice president, Ali Osman Mohammed Taha, and chairman of the Sudan People’s Liberation Army, John Garang, signed the peace agreement in a lavish ceremony in neighboring Kenya – where talks were based since 1997.

The north-south war has pitted Sudan’s Islamic government against rebels seeking greater autonomy and a greater share of the country’s wealth for the largely animist south. The conflict is blamed for more than 2 million deaths, primarily from war-induced famine and disease.

“Our people have experienced the bitterness of war…peace is indeed going to bring our country abundance,” President el-Bashir said after witnessing the signing. He said the agreement is not only between the rebels and the government but “a new contract for all Sudanese.”

Mr. Garang said the deal will transform the nation, guaranteeing equality for all races, ethnic groups, and religions for the first time in the country’s history.

“This peace agreement will change the Sudan forever,” Mr. Garang told a cheering crowd.

The deal calls for an autonomous south with its own army, national power and wealth sharing, religious freedom, and a new constitution during a six-year interim period. At the end of that period, the 10 southern states will hold a referendum on independence.

This deal is similar to one reached to end the north-south civil war that lasted from 1955 to 1972. That agreement was declared void by the northern government in 1983, setting off this war.

“This agreement came as a result of our struggle,” said a 29-year-old Sudanese man, Abraham Jok, who was recruited into the rebel army at the age of 12. “If this agreement is not like the one in 1972, we’ll be very sure we have our freedom.”

Speaker after speaker at the ceremony told the thousands of spectators that the massive problems facing the country – and the dramatic compromises made by both sides – will make implementing the agreement extremely difficult. There are dozens of militias in Sudan loosely allied to both the government and rebels who have not signed on to the deal.

And while the north-south conflict may be close to solved, there are major rebel groups in the north, east, and western Darfur region that are not part of the peace deal.

“A peace settlement that does not seriously address the causes of conflict in Darfur and other areas cannot be comprehensive, nor can it be sustained without community involvement,” said a spokeswoman for six international aid agencies working in Sudan. Cynthia Gaigals. “The next six months are the most fragile for this fledgling peace deal.”

Secretary of State Powell said America will not normalize relations with Sudan until there is peace throughout the country.

The deal “will close a dark chapter in the history of Sudan. …This is a promising day for the people of Sudan, but only if today’s promises are kept,” Mr. Powell said.

Later in Washington, President Bush added that “only the implementation of this agreement in good faith can result in long-term peace and development.

“As we celebrate this positive movement toward peace in the long-standing North-South conflict, we remember the conflict in Darfur and the suffering it causes. This comprehensive peace agreement should serve as an inspiration and model for both sides in their work toward negotiating a peaceful resolution of the Darfur conflict,” Mr. Bush said.

The Sudanese head of state promised to expedite peace talks on the separate conflicts.

“We are going to work together with our peace partners…to ensure peace prevails in every part of the country,” Mr. el-Bashir said.

The next step for the Sudanese government and the rebels will be for the Parliament in the Sudanese capital, Khartoum, and the rebel Parliament to ratify the agreement within two weeks. After that, negotiators will work on an interim national constitution.

Mr. el-Bashir and Mr. Garang both called on the international community to finance the peace agreement. Immediately after the ceremony, the U.N. World Food Program launched a $302 million emergency appeal to feed 3.2 million Sudanese over the next year.

U.N. officials have said the Security Council will review the peace agreement within two weeks, after which the council will adopt a resolution establishing a peace support mission for Sudan.

The mission’s key tasks will be to monitor a permanent cease-fire that came into effect on January 3 and protect its observers, as well as help the government and rebels reduce their forces and move them to designated areas, as agreed to in the protocols.