Prince William loves a cheeky Nando's.

The 37-year-old royal - who has Prince George, six, Princess Charlotte, five, and Prince Louis, two, with his wife, the Duchess of Cambridge - has revealed that whenever the policeman guarding him that loves their food is on duty, he'll often go and grab him a takeaway from the popular peri-peri chicken joint.

On the new documentary, 'Football, Prince William and our Mental Health,' an employee at one of the restaurants, Jamo, asked William: ''You like Nando's?''

And The Duke of Cambridge beamed: ''I like Nando's -- everyone likes a Nando's.''

Jamo was surprised by his response and quizzed him on when he last tucked into a Nando's meal.

Will replied: ''It was a while ago now.

''In fact, the policeman who's on with me again, he's the one who gets me the Nando's the whole time. It's his fault.''

William and Catherine love to have a takeaway every now and then, and previously revealed they love to relax with a curry while watching their favourite shows such as 'Game of Thrones' and 'Homeland'.

William: ''We're actually quite keen on box sets. We like to watch box sets ... We've watched 'Homeland', we're big fans of 'Homeland'. 'Games of Thrones' we've watched as well. Seems like everyone has seen it... ''

Catherine, 38, added: ''Absolutely and curry - definitely!''

William also confirmed their food doesn't get delivered and, instead, a member of staff picks it up for them.

He said: ''It doesn't get ordered to the palace. We go and pick it up, not ourselves.''

The couple's daughter Charlotte is also a lover of spicy food and is ''pretty good with heat''.

All members of the Cambridge household prefer different levels of spice, with her favouring the hottest meal.

Catherine said previously: ''It's so hard cooking curry with the family though.

''The children have a portion with no spice, [William's] is medium. And I quite like it hot.

''Charlotte is pretty good with heat.''

'Football, Prince William and our Mental Health' airs on BBC One from 8.05pm.