Britain's Prince William and Kate Middleton have been praised for their "unpretentious" approach to marriage.

The couple - who will marry at London's Westminster Abbey on April 29 in front of an estimated television audience of two billion people - have received commendation from Church of England head the Archbishop of Canterbury Dr. Rowan Williams, who will officiate their wedding, for their realistic approach to the future.

Speaking in a video on his official website, he said: "I've been very struck by the way in which William and Catherine have approached this great event. They've thought through what they want for themselves, but also what they want to say.

"They're responsible to the whole society, and responsible to God for their relationship. I think that they are deeply unpretentious people, and that message about taking that responsibility sensibly, realistically, courageously, comes over very strongly in conversation with them."

The religious leader added he hoped the pair would be given "strength" to show how a couple can live happily.

He said: "I hope they'll be given the strength and the persistence to go on showing the rest of us what's possible for the whole of their life together."