In the photo, the Princess of Wales appears to be wearing a recognisable long tunic-like top with trousers.
Earlier this week, the Duchess of Cambridge channelled Diana's look when she exited the plane upon landing at Pakistani Air Force Base Nur Khan.
Kate wore a turquoise blue bespoke dress with a draped neckline and matching pants.
The look appeared to be inspired by the traditional shalwar kameez, which according to Medium, consists of a pair of trousers and a tunic.
According to People, Kate's outfit was by Catherine Walker (a known favourite of Princess Diana).
Susan Kelley, editor and founder of fashion blog WhatKateWore.com, told the publication that she expected Kate would try out some culturally inspired looks on the royal tour of Pakistan,
“I think we will probably see at least one traditional shalwar kameez — the top and loose trousers look — from Kate on this trip,” Kelley told People.
“Diana wore that look multiple times in Pakistan and I think she has on occasion looked to Diana for inspiration while being careful not to copy her.”
This isn't the only tribute Prince William and Kate have made to Princess Diana on their tour of Pakistan.
On the third day of their tour, the royal couple followed in her footsteps by visiting the Chitral district of the Khyber-Pakhtunkhwa Province.