VATICAN CITY (Reuters) - Pope John Paul II moves a step closer to sainthood on Sunday when his successor beatifies him before an expected crowd of several hundred thousand people. Pilgrims from all over the world, many from the pope's native Poland, have flocked to Rome to witness the beatification mass and take part in the biggest event in the Italian capital since the late pope's funeral in 2005.
Groups carrying national flags and singing songs have gathered over the weekend where the ceremony will take place, in St Peter's Square, which is bedecked with posters and photos of the late pope.
Up to 200,000 people attended a prayer vigil on Saturday evening in the Circus Maximus, the huge oval once used by the ancient Romans for chariot races. Some Rome churches threw their doors open all night to give pilgrims a space to pray.
John Paul's successor Pope Benedict XVI will pronounce a Latin formula on Sunday declaring one of the most popular popes in history a "blessed" of the Church.
A place of honor is reserved for Sister Marie Simon-Pierre Normand, a French nun who suffered from Parkinson's disease but whose inexplicable cure has been attributed to John Paul's intercession with God to perform a miracle, thus permitting the beatification to go ahead.
The Vatican will have to attribute another miracle to John Paul's intercession after the beatification in order for him to be declared a saint.
Some 90 official delegations from around the world, including members of five European royal families and 16 heads of state, will attend the beatification.
They include Zimbabwean President Robert Mugabe, who has been widely criticized for human rights abuses in his country. Mugabe is banned from traveling to the European Union, but the Vatican -- a sovereign state -- is not a member of the bloc.
Pope John Paul's coffin was exhumed on Friday from the crypts below St Peter's Basilica and will be placed in front of the main altar. After Sunday's beatification mass, it will remain there and the basilica will remain open until all visitors who want to view it have done so.
It will then be moved to a new crypt under an altar in a side chapel near Michelangelo's statue of the Pieta. The marble slab that covered his first burial place will be sent to Poland.
John Paul's beatification has set a new speed record for modern times, taking place six years and one month after his death on April 2, 2005.
While the overwhelming number of Catholics welcome it, a minority are opposed, with some saying it happened too fast.
Liberals in the church say John Paul was too harsh with theological dissenters who wanted to help the poor, particularly in Latin America. Some say John Paul should be held ultimately responsible for the sexual abuse scandals because they occurred or came to light when he was in charge.
Ultra-Conservatives say he was too open toward other religions and that he allowed the liturgy to be "infected" by local cultures, such as African dancing, on his trips abroad.
The pope is being beatified on the day the Church celebrates the movable Feast of Divine Mercy, which this year happens to fall on May 1, the most important feast in the communist world.
The coincidence is ironic, given that many believe the pope played a key role in the fall of communism in Eastern Europe.