Pope XVI has arrived in the Spanish capital, Madrid, amid angry protests by thousands of people angry at the cost of the four-day visit.

The Pope is joining hundreds of thousands of young Catholics who have poured into the capital for World Youth Day.

The five-day celebration kicked off on Tuesday with an open-air Mass in Cibeles Square and will culminate with another Mass led by the Pope on Sunday.

After arriving at Madrid’s Barajas airport, the Pope told journalists: "The economy cannot function as a self-regulated economy. Man must be at the economy's centre, which is not profit but solidarity."

He also urged young Catholics not to be ashamed of their faith.

"With all my heart, I say again to you young people: let nothing and no one take away your peace; do not be ashamed of the Lord."

Up to a million pilgrims are expected to take part, including 4,000 Catholics from the UK who are being accompanied by the head of the Roman Catholic Church in England and Wales, Archbishop Vincent Nichols.

There were angry scenes in Madrid last night as protesters heckled pilgrims and clashed with police in the old city centre.

Some held banners declaring “Nothing for the Pope from my taxes”.

Protesters are angry at the cost of the Pope’s visit, estimated at around 50 million euros, at a time when the country is struggling with debt and an unemployment rate of 21%.

The 15-M “indignant” movement said in a statement: “We are not angry about the Pope’s visit, which some will agree with and others won’t, but rather over the financing of it with public money, especially at a time when many services are being cut because it’s necessary to curb government spending.”