Pope Francis marked his first Good Friday with a traditional torch-lit ceremony around the Colosseum in Rome and prayers for a Middle East "torn apart by injustice and conflicts".

The newly-elected Argentine pope presided over the re-enactment of the last hours of Jesus Christ's last hours, praying for Christians in the region and for "our Muslim brothers".

"Christians must respond to evil with good, taking the cross upon themselves as Jesus did," said Francis, who followed the ceremony from under a canopy overlooking the 2,000-year-old Roman amphitheatre.

The pope also referred to a visit to Lebanon last year by his predecessor Benedict XVI, who stunned the world by resigning last month at the age of 85.

"We saw the beauty and the strong bond of communion joining Christians together in that land and the friendship of our Muslim brothers and so many others," the 76-year-old pope said.

Brazilian, Chinese, Italian, Lebanese and Nigerian faithful took turns carrying a wooden cross around the Colosseum, where it is commonly believed that Christians were martyred.

Prayers read out at the ceremony were written by a group of Lebanese young people chosen by the Maronite Patriarch Bechara Rai, who was given the task by Benedict XVI.

"Come, Holy Spirit, to console and strengthen Christians, especially those from the Middle East so that, united in Christ, they may be witnesses of your universal love in an area torn apart by injustice and conflicts," read one of the prayers.

Another referred to the wars "which in our days devastate various countries in the Middle East".

"Let us pray that the displaced and the forced migrants may soon return to their homes and lands," it said.

A third prayer referred to Middle East Christians "stripped by various difficulties, sometimes to the point of persecution, and weakened by emigration", asking that they have "the courage to remain in their countries."

The Vatican has voiced concern over the fate of Christian minorities in many parts of the Middle East and the rise of radical Islam, as well as calling for an end to conflict in the region.

On Thursday, Francis celebrated mass in a youth prison, washing the feet of 12 inmates including two Muslims -- an unprecedented version of a traditional pre-Easter ritual.

The ceremony is usually held in a basilica in the city centre and commemorates the gesture of humility believed to have been performed by Jesus for his 12 disciples at their last meal.

Popes performing the ritual have usually washed the feet of priests.

Francis has already broken with several Vatican traditions, although he is yet to begin tackling the many problems assailing the Roman Catholic Church including reform of the scandal-ridden Vatican bureaucracy and bank.

Latin America's newly elected first pontiff has however set a markedly different tone from his predecessor, with a more open and informal style that is unusual in the Vatican halls of power.

The former archbishop of Buenos Aires, Jorge Mario Bergoglio, was known in Argentina for his strong social advocacy during his homeland's devastating economic crisis, his own humble lifestyle and his outreach in poor neighbourhoods.

Good Friday is the second of four intensive days in the Christian calendar culminating in Easter Sunday, which commemorates Christ's resurrection.

Vatican spokesman Federico Lombardi said the pope had shortened some of the lengthy Easter ceremonies as part of his "desire for simplicity".

On Saturday evening, the pontiff will take part in an Easter vigil in St Peter's Basilica.

The Vatican has said he will baptise four adult converts to the Catholic Church during the service -- an Albanian, an Italian, a Russian and a US national of Vietnamese origin.

On Sunday the Vatican's first non-European pope in nearly 1,300 years will celebrate Easter mass in front of tens of thousands of pilgrims in St Peter's Square and then pronounce the traditional "Urbi et Orbi" blessing to Rome and the world.