The election of Barack Obama as the first African-American US President could pave the way for the election of the first black Pope, according to a leading black American Catholic.

Wilton Daniel Gregory, 60, the Archbishop of Atlanta, said that in the past Pope Benedict XVI had himself suggested that the election of a black pontiff would "send a splendid signal to the world" about the universal Church.

Archbishop Gregory, who in 2001 became the first African American to head the US Bishops Conference, serving for three years, said that the election of Mr Obama was "a great step forward for humanity and a sign that in the United States the problem of racial discrimination has been overcome". Like Mr Obama Archbishop Gregory comes from Chicago, and was previously Bishop of Belleville, Illinois.

He said that recent Popes, beginning with John XXIII and Paul VI, had brought prelates "from all nations and races" to Rome to take up senior positions in the Curia, the Vatican hierarchy. This offered "an international vision of a Church rich in diversity", he told the Italian newspaper La Stampa.

Pope Benedict — whose next encyclical is on globalisation and social justice — had a "world outlook" as a theologian whose thought had "opened hearts and minds on five continents", Archbishop Gregory said. The former Joseph Ratzinger, who as a young man in his native Germany had witnessed "the horrors of the Second World War", spoke a "universal language".

Archbishop Gregory said that the next time cardinals gathered to elect a Pope they could "in their wisdom" choose an African pontiff. "My own election as head of the US Bishops Conference was an important signal. In 2001 the American bishops elected someone they respected regardless of his race, and the same thing could happen with the election of a Pope."

He said that in a papal conclave, the cardinal-electors were "guided by the Holy Spirit to choose the person who best responds to the exigences of the moment". At the last conclave in 2005, after the death of John Paul II, it was widely thought that the cardinals would choose a Third World pontiff, perhaps from Africa or Latin America.

The choice of Cardinal Ratzinger, who had been at John Paul II's side for over twenty years as head of the Congregation for the Doctrine of the Faith, was seen by many as a vote for a man who embodied continuity and had stressed the need to shore up the faith in the West itself in an age of secularism and materialism.

This week Pope Benedict XVI congratulated Mr Obama on his "historic" victory, offering his prayers for the President-elect "and for all the people of the United States".

Father Federico Lombardi, the Vatican spokesman, said that the Pope's message was "personal" and would therefore not be published. However he said that the papal message referred to the "historic occasion" of the election and congratulated Mr Obama, his wife and family.

"He assured him of his prayers that God would help him with his high responsibilities for his country and for the international community," Father Lombardi said. The Pope had also prayed that "the blessing of God would sustain him and the American people so that with all people of good will they could build a world of peace, solidarity and justice." The message was sent via Mary Ann Glendon, the US ambassador to the Holy See.