Prince William and his wife Catherine gather close friends and family on Wednesday for the christening of their baby son Prince George, in a low-key ceremony far removed from the global hype surrounding their wedding.

Queen Elizabeth II and the couple's parents and siblings will be among just 22 guests at the Chapel Royal at St James's Palace in London, along with seven godparents taken from William and Kate's circle of friends.

Prince George, the son of Britain's Prince William and his wife Catherine, will be christened on October 23, the royal family said on Friday.

The Archbishop of Canterbury Justin Welby, the head of the world's Anglicans, will perform the christening at the Chapel Royal in St James's Palace in London.