Prince William, Prince Harry and their significant others attended the annual Kensington Palace workers' Christmas party this week.

Prince William and Duchess Catherine

Prince William and Duchess Catherine

The Duke and Duchess of Cambridge, and Harry and his fiancee Meghan Markle, headed to the upstairs ballroom at Beach Blanket Babylon in Notting Hill, west London, for the bash.

A source told Mail Online the Palace forked out an estimated £110 a head for the 60-guest event, but party-goers were said to have had to bring their own alcohol after the restaurant's licence was reportedly recently revoked.

One of the restaurant's staff members is said to have told the publication the licence recently expired and they were in the process of applying for another.

Kensington Palace workers were able to choose from five main courses on the menu after consuming one of mushroom soup, avocado vignette or salmon for starters.

For dessert, revellers were able to have either chocolate cake, cheesecake or the traditional Christmas pudding.

On a weekday evening prior to the festive period, the ballroom is available for around £6,500, including food and soft drinks.

According to a source, Harry and Meghan left the event before William and Catherine.

It wasn't the first time Harry and William had headed out for the evening this week.

On Tuesday night (12.12.17), the siblings attended the London premiere of 'Star Wars: The Last Jedi'.

The pair both make cameo appearances in the much-anticipated new sci-fi movie and showed their support for its release by walking alongside Stormtroopers at the spectacle.