Cardinal Camillo Ruini, vicar for the Diocese of Rome, who under church canons is to announce the death of the pope, has arrived at the Vatican, according to AFP.
Pope John Paul was in a "very grave" condition on Friday and appeared close to death after suffering cardio-circulatory collapse and shock, the Vatican said in a statement, as cited by international agencies.
According to the statement the Pope was still "conscious, lucid and tranquil" on Friday morning.
Late on Thursday the Vatican spokesman said that Pope John Paul II was administered last rites of the Roman Catholic Church - a clear sign that the pontiff is on the verge between life and death.
However, sacrament does not necessarily mean that the Pope is dying, as last rites are commonly given to people who are seriously ill as well. The Pontiff has previously received the sacrament after he was shot by a would-be assassin in 1981.
The ailing Pontiff is suffering from a very high fever caused by a urinary infection and is being treated by antibiotics.
"He's ill, very ill," Italy's Ansa news agency quoted an unnamed medical source as saying on Friday.
"The world is in anguish. The Pope is fading away," was the headline in one Italian newspaper, Il Resto del Carlino.
Reports say the Pope was not taken to hospital, as he was too frail to survive being moved.