The former Archbishop of Canterbury, Baron Williams of Oystermouth, has recalled with humour his experience of delivering sermons to the Duke of Edinburgh, who died last Friday at the age of 99.

Baron Williams said it was a "very terrifying experience" to preach in front of Prince Philip because of his strong feelings on the length of the sermon.

"He made it very clear what he thought a good sermon required and what it didn't require, and it certainly didn't require more than eight minutes in delivery," he said.

"I was told very, very firmly that going over eight minutes would probably land me in the Tower of London!"

Baron Williams, who was the guest speaker at the Religion and Media Centre's 'Exploring Belief' festival on Monday, said the duke "would listen very, very carefully" and "argue very closely" over the points in the sermon.

He also recalled being "really struck" by the duke's familiarity with the Greek New Testament - Prince Philip was the son of Prince Andrew of Greece and Denmark.

Asked whether he agreed that there was "no parole" from life as a royal - a reference to recent comments by his successor Justin Welby - Williams said, "None at all, no ... As Woody Allen famously said, 90 per cent of life is just turning up.

"I think that's more true for the royals than anybody else and to do that with a measure of grace and humanity is quite an achievement."

Prince Philip died peacefully last Friday morning with the Queen by his side.

A national minute's silence is to be held in his honour at 3pm on Saturday, the same day as his funeral which will be a small affair with only 30 people present because of Covid-19 restrictions.