BBC News with Jonathan Wheatley

In a historic speech at the houses of parliament on the second day of his visit to Britain, the Pope has said the world of faith and the world of secular rationality need one another

for the good of

civilization.

He said those who called for the voice of religion to be silenced failed to understand the legitimate role of religion in public life.

A little later, Pope Benedict publicly shook hands with an Anglican woman priest for the first time as he became the first Pope to enter Westminster Abbey.

With more on the Pope's speech, here is our religious affairs correspondent Robert Pigott.

This was one of the most important speeches of Pope Benedict's

papacy

, and he used it to warn that the very health of democracy that Britain had planted all over the world was

in jeopardy

because religion was being excluded from national debate. In a speech clearly intended to be heard in developed countries across the world, Pope Benedict warned that democracy relied on the use of reason, but that its reasoning was being

distort

ed by ideology and changing social fashions. "Reason," said the Pope, "needed the

light shed on

it by religion with its unchanging teaching based on the fundamental nature of people."

The United Nations has appealed for millions of dollars more in aid to help Pakistan recover from last month's devastating floods. The UN says it needs an additional $1.5 billion, its largest-ever aid appeal for a natural disaster. Barbara Plett now reports from the United Nations in New York.