Pope Benedict XVI pledged his allegiance to his future successor and appealed for unity within the Catholic Church, during a historic farewell with cardinals yesterday, hours before resigning from the papacy.

Benedict officially steps down at 8 p.m. end of his papacy will be marked by the closure of the gates of the palace of Castel Gandolfo, the papal residence on the outskirts of Rome where he is to relocate over the coming weeks.

He told cardinals that he would pray for the Holy Spirit to assist them in the choice of a new pope, to whom “I promise my unconditional reverence and obedience.’’

Elected on April 19, 2005, Benedict is the first pontiff to resign in almost 600 years. His decision had raised questions about how the Catholic Church will deal with the unprecedented situation of having a former pope alive alongside his successor.

Cardinals will hold preliminary meetings on Monday, with a view to set a date for the conclave, the closed-door assembly held in the Sistine Chapel tasked with electing a successor.

The aim is to have a new pope by Easter, which falls on March 31 this year.

During his papacy, Benedict had to deal with the alleged cover-up of child sex abuse by priests and the VatiLeaks affair – the publication of confidential papal papers which shed light on suspected cronyism, corruption, power struggles and scheming inside the Vatican.

He insists his decision to leave the papacy was dictated by his diminishing strength from old age and had nothing to do with Vatican scandals.

Echoing remarks made about the ups and downs of his papacy during his last public audience, Benedict told the cardinals that he had gone through “wonderful moments of shining light as well as moments in which some clouds gathered in the sky’’.

He did not refer to the alleged Vatican intrigues, but he said that for all its diversity, “the College of Cardinals should be like an orchestra following a superior and concordant harmony.’’

Benedict also struck an optimistic note about the future of the Catholic Church, describing it as “a living being animated by the Holy Spirit,’’ as he recalled the large crowds that had turned up to hear him in St Peter’s Square last Wednesday.

During yesterday’s farewell ceremony, the 85-year-old pontiff made a brief speech and then stood up for over half an hour while cardinals took turns to pay their respects.

Appearing frail but alert, he stopped the process briefly to drink a glass of water.

United States Cardinal Roger Mahony was among those who greeted the pope, in spite of an online petition that had urged him to stay away from Rome due to his past attempts to shield priests who sexually abused children. Because of this, he has already been stripped of all public duties.

“Holy Father, with deep love we always tried to accompany you along your path,’’ Cardinal Angelo Sodano, the Dean of the College of Cardinals said.