VATICAN CITY (CNS) -- Corruption, ethnic tensions, indifference and injustice must be tackled to bring lasting peace to Sudan, Pope Benedict XVI told the country's bishops.

"Treaties and other agreements, indispensable building blocks in the peace process, will only bear fruit if they are inspired and accompanied by the exercise of mature and morally upright leadership," the pope said.

Meeting the bishops of Sudan March 13 at the end of their "ad limina" visits to the Vatican, Pope Benedict praised their work in promoting peace, reconciliation, economic justice and human rights through the rule of law.

He also thanked them for their tireless efforts in assisting the poor and helping them achieve a life of dignity and self-respect.

Sudan's two-decade-long war ended with a peace treaty that was signed between the Muslim-dominated government and the Sudanese People's Liberation Movement in January 2005.

Pope Benedict said, "The effects of violence may take years to heal, yet the change of heart which is the indispensable condition for a just and lasting peace must even now be implored as a gift of God's grace."

"If peace is to plant deep roots, concrete efforts must be made to diminish the factors contributing to unrest, particularly corruption, ethnic tensions, indifference and selfishness," he said.

The pope also expressed appreciation of the bishops' efforts in maintaining good relations with their Muslim neighbors and asked the bishops to "stress the values that Christians share in common with Muslims as the basis for that 'dialogue of life' which is an essential first step toward genuine interreligious respect and understanding."

Bishop Rudolf Deng Majak of Wau, president of the Sudanese bishops' conference, said divisions along ethnic, racial, and religious lines still exist among the Sudanese.

Conflict in Sudan will be averted only when people can accept each other with mutual respect, he told the Vatican newspaper, L'Osservatore Romano March 12.

One problem the country faces is that some people would like Sudan to become a place just for Muslims or just for Christians, he said. The church, however, would like Sudan to be a place that is open to everyone, he said.

While respect for religious freedom has grown in the southern part of the country since the peace treaty took effect, religious liberty is still severely restricted in northern Sudan, where Christians and other non-Muslims are subject to Islamic law. According to the 2005 treaty, Islamic law, known as Shariah, is not applied in the more religiously diverse southern part of the country.

People in southern Sudan are scheduled to vote in a referendum in January 2011 on whether their region should be independent or remain a part of Sudan.

Bishop Deng said he believes Sudan should be one country made up of federated states on the model of the United States, Brazil and India, and that the government has a responsibility to highlight the advantages of a united nation.

He said such a system would allow the Sudanese to "live together in a nation given to us by God, at peace with itself and accepting of its children as they are."

But "in order to make unity seem attractive, it's necessary to recognize diversity and the rights of all people even if they don't belong to the same culture, same religion and the same traditions," he said.

Bishop Macram Gassis of El Obeid told Catholic News Service March 10 that Shariah law in the North "is not working" because it does not acknowledge that the region already is multiethnic and multireligious.

He said many bishops have been caught "unprepared in a way" to deal with Islam because many do not understand its tenets and have not even "opened the Quran just to see what's inside."

The bishop also said the presence of the Catholic Church is crucial for peace in Sudan.

"I firmly believe that the church is the hope of my people," he said.

"Even during the peak of the violence and the killing, the presence of the church always gave hope not only to the Catholics, but to all the tribes, to all the creeds, and our very presence with them was always an assurance that we are together; don't be afraid, we are together," he said.

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