Cardinals are due to meet on Tuesday to plan Pope Francis' funeral, which leaders from around the world will attend ahead of a conclave next month to elect a new head of the Roman Catholic Church.
The Vatican had said that the 88-years-old pontiff unexpectedly died on Monday after suffering a stroke and cardiac arrest, ending an often turbulent reign in which he repeatedly clashed with traditionalists and championed the poor and marginalised.
DAILY POST reports that the cleric spent five weeks in hospital earlier this year for double pneumonia.
He, however, returned to his Vatican home almost a month ago and had seemed to be recovering, appearing in St. Peter's Square on Easter Sunday.
The pope's sudden demise set in motion ancient rituals, as the 1.4-billion-member Church started the transition from one pope to another, including the breaking of the pope's “Fisherman's Ring” and lead seal so they cannot be used by anyone else.
“We want to thank the Lord for the gifts he has given to the whole Church with the apostolic ministry of Pope Francis, a pilgrim of hope,” Cardinal Mauro Gambetti, who led prayers in St. Peter's Square on Monday evening said.
All cardinals currently in Rome have been invited to gather in the Vatican at 9 a.m (0700 GMT), where they were expected to make funeral plans.
President Donald Trump of the United States, who clashed repeatedly with the pope about immigration, said he and his wife would fly to Rome for the event.
Among other heads of state set to attend were Javier Milei, president of Francis' native Argentina.
According to the Vatican, the ceremony is expected to take place sometime between Friday and Sunday.
In a break from tradition, Francis confirmed in his final testament released on Monday that he wished to be buried in Rome's Basilica of Saint Mary Major and not St. Peter's Basilica.
The gathering of cardinals will also review the day-to-day running of the Church in the period before a new pope is elected.
DAILY POST reports that a conclave to choose a new pope normally takes place 15 to 20 days after the death of a pontiff, meaning it should not start before May 6.
At least 135 cardinals are eligible to participate in the highly secretive ballot which can stretch over days.
However, at present, there is no clear frontrunner to succeed Francis.
