The uncle of the Duchess of Cambridge has admitted hitting his wife in the face and knocking her unconscious after a drunken argument on their way home from a charity event.

Gary Goldsmith, 52, used a closed fist to attack his wife Julie-Ann outside their home in Wimpole Street, central London.

A taxi driver who took the pair home described how Mrs Goldsmith fell to the floor after he threw a “left hook” at her.

Goldsmith - who attended the wedding of Prince William and Catherine Middleton in 2011 - pleaded guilty to one count of assault by beating at Westminster Magistrates' Court on Tuesday.

He has now been banned from returning home and is likely to be made the subject of a restraining order preventing him from going near his estranged wife.