BUENOS AIRES (AFP) - World leaders and Catholics hailed the election of Jorge Mario Bergoglio from Argentina as the first Latin American pope on Wednesday, calling on him to work for the promotion of peace.

United States (US) President Barack Obama and Argentina's President Cristina Kirchner led congratulations from across the Americas, where Catholics rejoiced that one of their own will lead the church's 1.2-billion-strong flock.

In Buenos Aires, the faithful attending mass at the capital's main cathedral on the historic Plaza de Mayo erupted in cheers and gave a standing ovation upon learning from Vatican City of the 76-year-old's elevation.

"As the first pope from the Americas, his selection... speaks to the strength and vitality of a region that is increasingly shaping our world," Mr Obama said in a statement, hailing Francis I as a "champion of the poor".

"Just as I appreciated our work with Pope Benedict XVI, I look forward to working with His Holiness to advance peace, security and dignity for our fellow human beings, regardless of their faith," he said.

US Vice President Joe Biden, a Catholic, has been chosen to lead the US delegation to the new pope's inauguration mass on Tuesday, a White House official told AFP.

Ms Kirchner, who is Catholic but does not have a warm personal relationship with the new pontiff, wished the 76-year-old Jesuit a "fruitful pastoral mission".

She noted that he had "tremendous responsibility on his shoulders, seeking justice, equality, brotherhood, and peace among mankind."

United Nations (UN) Secretary General Ban Ki Moon said the UN and the Roman Catholic Church shared the "common goals" of promoting peace, social justice and human rights, and the eradication of poverty and hunger.

"We also share the conviction that we can only resolve the interconnected challenges of today's world through dialogue," Mr Ban said.

French President Francois Hollande said Paris looked forward to pursuing a "confident dialogue" with the Holy See.

And European Union President Herman Van Rompuy and European Commission head Jose Manuel Barroso urged the pope to work to bring the "world's people and religions closer together".

In Latin America, the leaders of Colombia, Ecuador, Mexico joined the clergy in hailing Bergoglio, who was elected after five rounds of voting in the Vatican - one more than when predecessor Benedict XVI was chosen in 2005.

"Long live Francis I!" exulted Ecuador's President Rafael Correa on his Twitter account - one of millions of tweets sent about the historic election that ended with white smoke billowing out of a chimney atop the Sistine Chapel.

"We are extremely happy because our Lord has cast his eyes on Latin America, and we are extremely grateful to God for that because we have a Latin American pope," said the Archbishop of San Salvador, Jose Luis Escobar.

In Brazil, some expressed disappointment that Cardinal Odilo Scherer, the archbishop of Sao Paulo who had been considered a frontrunner, was not elected.

"We wanted a Brazilian pope, but the Argentines are our brothers, our neighbours. It's all good," Mr Rosivaldo dos Santos, 38, told Agence France-Presse.

In Africa, where the number of Catholics is steadily growing, the president of the Southern African Catholic Bishops Conference said that, while some had hoped for a younger pontiff, all expect "great things" from Pope Francis.

"The symbolism of choosing a pope from Latin America delights and touches us, most particularly in developing countries," said Archbishop Stephen Breslin.

Father John Dingi, of St Matthew's Catholic Cathedral in downtown Khartoum, where Christians are a tiny minority in Islamist-run Sudan, also expressed his joy.

"We are very happy," Fr Dingi said. "It's good because, you see, Christianity is now growing very fast in Africa, in Latin America, in Asia." Justin Welby, the new Archbishop of Canterbury and leader of the world's Anglicans, wished "every blessing" to the new pope and said he looked forward to meeting him.

The new pope was sure to face continuing pressure to ensure no further sex abuse by pedophile priests or cover-ups by senior clergymen.

The Survivors Network of Those Abused by Priests warned that Jesuits have a "troubled track record on children's safety" and urged Pope Francis to seize an "enormous opportunity and duty to help prevent heinous assaults against kids".