Pope Francis will preside Thursday over the funeral of his predecessor Benedict XVI at the Vatican, an unprecedented event in modern times expected to draw tens of thousands of people.

Almost a decade after Benedict became the first pontiff in six centuries to resign, his successor will deliver the homily in the vast St Peter's Square before his body is laid in the papal tombs beneath St Peter's Basilica.

The German emeritus pope was no longer a head of state but world leaders including German Chancellor Olaf Scholz will attend the funeral, alongside European royals and more than 4,000 cardinals, priests and bishops, according to the Vatican.

Queues of people, including many priests and nuns, formed before dawn in thick fog to enter the square, across which thousands of chairs have been laid out.

"Benedict is a bit like my father, so I had to pay homage to him... to learn his faith," said Cristina Grisanti, a 59-year-old from Milan who arrived at 5:30 am.

She hailed the former pope's "purity, his candour, his mildness".

Benedict, born Joseph Ratzinger, died on Saturday aged 95, bringing an end to an unprecedented situation of having two "men in white" - he and Francis - living in the Vatican.

An estimated 195,000 people have already paid their respects during three days of lying in state at the basilica, the Vatican said.

On Wednesday evening, he was transferred into a cypress coffin for the funeral, which begins at 9:30 am (0830 GMT) and which officials expect will draw 100,000 people.

Portugal has declared a national day of mourning on Thursday, while in Italy, flags will be flown at half-mast on public buildings.

In Germany, church bells will ring out at 11:00 am in memory of the first German pope in 1,000 years.

Two popes

Francis - who praised the "noble, kind" Benedict after his death at the monastery - now has the unusual experience of presiding over his funeral.

The last time a pope presided over the funeral of his predecessor was in 1802, when Pius VII led the ceremony for Pius VI - but the circumstances were very different.

Pius VI died in 1799 in exile, a prisoner of France, and was buried in Valence. His successor had his remains exhumed and brought back to Italy, before he was treated to a papal funeral at St Peter's.

Security operation

Around 1,000 police will provide security at the funeral, bolstered by numerous civilians from Italy's civil protection service, while more than 1,000 journalists are accredited.

The only official delegations are from Germany and Italy. Other dignitaries, including Belgian and Spanish royals, the presidents of Lithuania, Poland, Portugal, Hungary, Slovenia and Togo, and the premiers of the Czech Republic, Gabon and Slovakia among others are attending in a personal capacity.

Before being laid in the crypt, his cypress coffin will be placed first inside a zinc coffin, then a wooden case.

As is traditional, coins and medals minted during his papacy and a written text describing his pontificate, sealed in a metal cylinder, will be placed alongside his body.