Kate Middleton debuts an emerald green Temperley London gown at 2017 National Portrait gala

Duchess Kate Middleton almost never fails to make a lasting impression with her sartorial choices especially when it comes to her favourite fashion designers. This time, the royal wore an emerald floor-length lace gown by the London-based designer Temperley.

Unfailingly, she outshined all the other celebrities as she made an appearance at the 2017 Portrait Gala in London on Tuesday.

Kate, who has been a patron of the National Portrait Gallery since 2012, was attending to view the latest exhibitions of Howard Hodgkin: Absent Friends, and Gillian Wearing and Claude Cahun: Behind The Mask, Another Mask.

The royal mother-of-two complemented her emerald green look with a glittering golden clutch worth £195 by Wilbur & Gussie.

Keeping with the hues, a green amethyst and diamond Candy earrings by Kiki McDonough added a hint of bling to her glamorous outfit.

While Kate's rather luxurious style for the evening appeared to be in contrast with her usually chic yet high-street choices, what remained a constant was her signature hair. She let her brunette locks open, tousled in loose curls.

Joining the royalty at the art gala was a host of A-listers including Alexa Chung, Sophie Ellis-Bextor and Samantha Cameron. The fashion forward stars held their own in off-shoulders, bright colours and structured patterns at the event.

Interestingly, the art event turned into a more personal meet-up, when the Duchess of Cambridge was introduced to fellow parents Richard Found and Jane Suitor, whose child goes to the same school that is expecting Prince George in September.

As the conversation turned personal, the couple apparently informed Kate that it was a "great school".

"We were chatting about Thomas', the school George will be going to," Mr Found said later on. "We're parents there as well. She just said 'I may see you at the school gates'."

The royalty was even spotted speaking with Phillip Chung, father of British TV personality and model Alexa. Apparently the mother of Prince George and Princess Charlotte is gathering a personal collection of her own that includes her children's artistic works.