Pope Benedict XVI celebrated his first Easter Sunday as pontiff, praying for peace in Iraq, negotiated solutions to the world's nuclear disputes and dialogue between Israel and the Palestinians.

Looking tired, Benedict led nearly 100,000 pilgrims, tourists and Romans in Mass in St. Peter's Square. His 79th birthday coincided with Easter, when Christians commemorate the resurrection of Jesus Christ after his crucifixion.

"Today, even in this modern age marked by anxiety and uncertainty, we live the event of the resurrection, which changed the face of our life and changed the history of humanity," Benedict said in the traditional "Urbi et Orbi" message — Latin for "to the city and to the world."

From the central balcony of St. Peter's Basilica, the pontiff reviewed conflicts around the globe to rousing cheers and applause.

"In Iraq, may peace finally prevail over the tragic violence that continues mercilessly to claim victims," Benedict said, pausing as the crowd applauded.

"I also pray sincerely that those caught up in the conflict in the Holy Land may find peace, and I invite all to patient and persevering dialogue, so as to remove both ancient and new obstacles," the pope said.

"May the international community, which reaffirms Israel's just right to exist in peace, assist the Palestinian people to overcome the precarious conditions in which they live and to build their future, moving toward the constitution of a state which is truly their own," he added.

He also prayed for resolutions to global nuclear crises, though he did not name specific countries. Disputes over the nuclear programs of Iran and North Korea have embroiled many countries and are at an impasse.

"Concerning the international crises linked to nuclear power, may an honorable solution be found for all parties, through serious and honest negotiations," Benedict said.

Benedict also called on world leaders to promote racial, cultural and religious harmony "to remove the threat of terrorism."

The pope touched on the humanitarian crisis in Sudan's Darfur region and conflicts in other parts of Africa. He said that in Latin America, millions of people needed better living conditions and democratic institutions.

When the faithful read out prayers during the Mass, a woman speaking in French prayed for the pope. She offered a birthday wish and prayed that Benedict receive peace and the comfort of "serene" days.

Benedict wished the faithful a joyous holiday in 62 languages.

His wishes in Italian referred to Italy's political stalemate, in which conservative Premier Silvio Berlusconi has refused to concede defeat to center-left rival Romano Prodi in the extremely narrow April 9-10 elections.

"In the particular moment that Italy has been living through in these months, may the risen Lord bring serenity to the national community and strengthen those who work to serve it," Benedict said.

Benedict's predecessor, John Paul II, died six days after Easter last year. He was so weak during his final illness that he was unable to address faithful in the square on Easter, only raising his hand in blessing.