In preparation for beatification Sunday, Pope John Paul II's coffin has been removed from the crypt under St. Peter's Basilica and placed near St. Peter's tomb.

The coffin will be displayed before the main altar during the ceremony and then re-interred elsewhere. Also on display will be a vial of blood taken from the pontiff before he died April 2, 2005, at age 84. He had battled Parkinson's disease.

Beatification is the Roman Catholic Church's first step to sainthood. The BBC has a Q&A.

Attending Sunday's ceremony will be 22 heads of state, including Zimbabwean President Robert Mugabe, who will have to defy a European Union travel ban to reach the sovereign Vatican.