Huge crowds have gathered in Vatican City to see a historic ceremony where two popes - John Paul II and John XXIII - are declared saints.

A Mass co-celebrated by Pope Francis and his predecessor Benedict was watched by roughly one million pilgrims and a vast TV and radio audience.

Nearly 100 foreign delegations are attending, including royal dignitaries and heads of state and government.

It is the first time two popes have been canonised at the same time.

Correspondents say the move is being seen as an attempt to unite conservative and reformist camps within the Roman Catholic Church.
Pilgrims poured into Rome and special bus, train and boat services ferried many more into the city early on Sunday morning for the two-hour ceremony which started at 10:00 local time (08:00 GMT).

Some had bagged places to sleep overnight as close as possible to St Peter's Square, hoping to be among the first in when it opens to the public.

Giant screens have also been erected in nearby streets and elsewhere in the city for those unable to get into the square.

"We've been counting down the days. This is a once-in-a-lifetime experience," said one pilgrim from Poland, John Paul II's home country.

"We're already hoarse from singing," he told AFP.

The Vatican confirmed on Saturday that 87-year-old Benedict XVI - now officially titled Pope Emeritus - would make a rare public appearance alongside his successor.

He will co-celebrate, which does not mean he will go to the altar," a Vatican spokesman said.

"We will all be happy to have him there."

Benedict XVI became the first pope to resign for 600 years when he quit for health reasons a year ago.

The process of saint-making is usually long and very costly.

But John Paul II, whose 26-year reign ended in 2005, has been fast-tracked to sainthood in just nine years.

Many among the huge crowds that gathered as he lay dying cried out "santo subito", which means "sainthood now".

By contrast Italian-born John XXIII, known as the Good Pope after his 1958-63 papacy, had his promotion to full sainthood decided suddenly and very recently by Pope Francis.

The BBC's David Willey in Rome says there was a political dimension to this.

By canonising both John XXIII - the pope who set off the reform movement - and John Paul II - the pope who applied the brakes - Francis has skilfully deflected any possible criticism that he could be taking sides.