Robbie Williams and wife Ayda Field pose in each other's clothes for special night in

Robbie Williams and wife Ayda Field raided each other's wardrobes on Friday and showed off their new looks on Instagram – leaving fans in hysterics.

"@robbiewilliams We've swapped clothes and fragrances...it must be FORMAL FRIDAY #switchingitup #whenhisbecomeshersandvisaversa#ismelllikeacactus #androbbielooksbetterinmydressthanido #formalfriday AWxx," the mother-of-four commented alongside a picture of Robbie and her wearing each other's clothes.

© Photo: Instagram

Singer Robbie, 44, could be seen pouting to the camera whilst wearing a green dress with a high slit and deep V neck. He accessorised his look with black pearl slippers and a pink eye mask. Ayda, on the other hand, wore one of the singer's summer suits and brown Gucci slippers.

MORE: Robbie Williams shares glimpse inside his children's incredible playroom

Fans were delighted with the swap, with one commenting: "Nice legs guys! I am starting to get used to this... love the posts on Friday," whilst another one wrote: "A word for your hubby…décolletage (you’re also brave putting your feet in those Gucci slippers)."

Earlier this month, Ayda and Robbie introduced a genius concept to help them feel slightly more 'normal' in these worrying times – "formal Fridays". The couple shared a gorgeous snap on Instagram of themselves dressed-up to the nines, with Robbie wearing a blue checked suit and Ayda in clashing animal print and florals.

© Photo: Instagram

Captioning the post, she wrote: "@robbiewilliams Shave your legs, wash your hair, cause it's officially FORMAL FRIDAYS at the Williams House #ourhouse #formalfridays #whynot #quarantinelife #stayhome AWxx." Fans of the couple loved the idea and took to the Instagram comments to say so. One follower simply said: "Brilliant idea!" while another gushed: "Wow you two look gorgeous xx." A third added: "Fabulous... love you guys looks like so much fun living with the Williams’s family."

© Photo: Instagram

Robbie and Ayda had a fun afternoon, but they soon returned to parenting duties. After posting the hilarious post on her grid, Ayda took to her stories to share a picture of her children Charlie and Teddy's Friday night plans. In the snap, several pillows, a duvet and toys could be seen laid out on the floor of their bedroom. "Sleepover…" she wrote across the image.