The store features a quirky design complete with oversized ice creams in bright colours, and it stocks a range of Wall’s products.
These include all of the classics along with new additions such as the Cornetto Peanut Butter Love and Cookies 'n' Dream, as well as Magnum’s new Pink and Black varieties.
The activation forms part of the brand’s 'Goodbye Serious' campaign, which it is running throughout the summer months.
Louise Morley, assistant brand manager OOH Ice cream at Wall’s, told Event: "Our ‘Goodbye Serious’ campaign is all about encouraging consumers to say goodbye to the seriousness of everyday life.
"The campaign uses cheeky one-liners, bright colours and beautiful product shots to disrupt people on their daily commute and remind them of their love for ice cream. The pop-up store brings daily commuters an engaging Wall’s ice cream experience with fun props and activities."
The pop-up will visit Westfield Stratford from 8 August to 6 September, and Morley explained shoppers can expect a special event to launch the store.
"On 8 August, we will be holding a launch event for the Stratford Westfield store with a surprise comedian who will be running a live copy-writing event."
Agency Hot Pickle designed the brand's activation, meanwhile N2O are handling the staffing element.
The ice cream pop-up first stopped off at Victoria Station in June.
Ice cream brands Magnum and Ben & Jerry's are also activating this summer. Magnum has opened a Pleasure Store at London's Covent Garden, meanwhile Ben & Jerry's is hosting a pedal-powered film screening event from 31 July to 2 August.