Pope Benedict XVI has arrived in Scotland for a historic state visit clouded by a row sparked by one of his aides who described Britain as an "aggressively" secular country".
The Pope was welcomed at the airport by the Duke of Edinburgh, church dignitaries and a Guard of Honour of the Royal Regiment of Scotland. He was then greeted at Edinburgh at Queen Elizabeth.
The head of Catholics in England and Wales said Cardinal Walter Kasper's comments were "inexplicable" and did not reflect the Pope's own opinion.
Benedict's four-day visit, only the second by the head of the Roman Catholic Church since English King Henry VIII broke with Rome in 1534, is aimed at improving frayed ties between Anglicans and Catholics.
But even before the row over Kasper's comments to a German magazine, there was strong opposition to the Pope's visit, with protests planned against his views on a range of issues including clerical child sex abuse.
After his meeting with the Queen the Pope will address 65,000 pilgrims in an open-air mass at Bellahouston Park in Glasgow.
Before the Mass, Benedict will bless a nine-year-old boy who wrote to the pope asking him to help stop his cancer from returning.
In an unprecedented move, pilgrims must pay up to 25 pounds (30 euros, 39 dollars) to attend the masses as a contribution towards the 20-million-pound cost of the visit.
The Pope will also visit London and the central English city of Birmingham.
The highlight of the trip will be a beatification mass for 19th-century English cardinal John Henry Newman, and will also feature symbolic prayers with the Archbishop of Canterbury Rowan Williams, the head of the world's Anglicans.
Kasper's comments to Focus magazine ensured a fresh round of controversy even before Benedict touched down.
"England is a secularised, pluralistic country these days," he told the magazine.
"When you land at Heathrow Airport, you sometimes think you might have landed in a Third World country.
"In England in particular, an aggressive neo-atheism has spread," he added.
Following the remarks, the Vatican said the cardinal had dropped out of the entourage accompanying Benedict for health reasons.
It insisted Kasper's remarks had "no negative intent or dislike" for Britain.
But England's top Catholic, Archbishop of Westminster Vincent Nichols, told the BBC: "On face value I find the remarks of Cardinal Kasper quite inexplicable.
"This is a very diverse country and we rejoice in that diversity."
The controversy of the abuse of children by Catholic priests has also loomed large ahead of the visit.
On the eve of the trip, British victims of clerical abuse issued a demand on for the pope to go further than offering an apology.
Peter Saunders, of the National Association for People Abused in Childhood, said: "We need the pope to say, 'I will hand over all the information I have about abusing priests wherever they are in the world.'"
The Pope is widely expected to meet victims of abuse during his visit.
Benedict will also try to ease tensions with Anglicans on a visit that comes just 11 months since the Vatican offered to take in dissident Anglicans angered by their church's moves to consecrate female bishops.