A £4m refurbishment, the first in 10 years, will be completed by June.

The makeover of the landmark store and its products will “transform” it ahead of the arrival in London of an expected 5.5 million visitors a day during the summer sports spectacular and an associated spending spree expected to total £100m in the West End alone.

Hamleys head of retail and marketing Nigel Wheatley said the refit was not directly related to the Olympics but the opportunity offered by London’s hosting of the games had added momentum. Two revamped floors have already opened.

Wheatley said: “This refit is a total root and branch of the store. We want to be the best toy store in the world and we’re on track. We have travelled all over the world and there is nothing like us.”

There has been a focus on strengthening Hamleys’ own-brand among the well-known toy labels stocked and on improving the customer journey.

On the remodelled fifth floor, which includes a footfall-driving Lego area, Hamleys has just unveiled Scrumpalicious – an own-brand sweet shop which will have product from around the world.

It has also introduced two new concessions, Candy Cakes – offering cupcakes – and milkshakes by Shaketastic, which has created a Hamleys shake decorated with 23-carat gold and selling at £16.

Hamleys is making its stairways more accessible to improve customer flow, enabling short-stay shoppers to buy and go.

On the ground floor, Hamleys plans to introduce four mobile tills, which will enable staff to carry out transactions using tablet computers designed to reduce queuing times.

Wheatley said: “We want the customers to enjoy the shopping experience more and we needed the shop to be able to handle the volume of customers.”

Hamleys’ pre-school range has been moved from the second floor to the more accessible first floor, which will be unveiled next week.