Pope Benedict XVI, centre, prays during the Palm Sunday mass in Saint Peter's Square at the Vatican. (Tony Gentile/Reuters)

Christians around the world observed Palm Sunday as the Roman Catholic church grappled with a clerical abuse scandal that has spread across Europe to the Pope's native Germany.

Palm Sunday commemorates Christ's entry into Jerusalem and is the start of the church's Holy Week, which includes the Good Friday re-enactment of Christ's crucifixion and death and his resurrection on Easter Sunday.

During the Palm Sunday homily, Pope Benedict XVI made no mention of the abuse scandal, which has drawn new attention to the church's handling of cases of pedophile priests.

But one of the prayers, recited in Portuguese, was "for the young and for those charged with educating them and protecting them."

New York's Archbishop Timothy Dolan spent about five minutes on the topic at Saint Patrick's Cathedral, defending the Pope and saying he is being unjustly targeted by the media.

The Pope has been accused of ignoring warning signs of an abusive priest in Wisconsin while he was a cardinal.

The Vatican denied there was a coverup in the church's handling of the priest accused of molesting as many as 200 deaf boys in Milwaukee.

In recent weeks, Germany was rocked by a sex-abuse scandal at Catholic and secular schools after more than 250 people came forward to say they were molested.

Last year, an investigation in Ireland revealed church leaders had protected priests suspected of sexually abusing children in the Dublin archdiocese for decades.

Last Monday, the Regensburg diocese in eastern Germany said it was investigating four priests and two nuns for allegations that they sexually abused children decades ago.

With files from The Associated Press