People have become unwittingly reliant on modern slavery for cheap goods and illicit pleasures, Cardinal Vincent Nichols has said.

Warning of a return to slave-driven economies, the Cardinal Archbishop of Westminster said slavery was again becoming "one of the most profitable criminal activities in the world."

He said that although it was an evil comparable in enormity to child abuse, ordinary people often failed to realize how they were sometimes "part of the chain of supply and demand" that has led to an estimated 40 million people – a third of whom are believed to be children – trapped in slavery around the world.