NEW YORK, United States — Pandora, the world's biggest jewellery maker, will relaunch its brand at an event in Los Angeles later on Wednesday as it tries to attract middle-class shoppers seeking affordable luxury back to its stores.

The Denmark-based company, best known for its customisable silver charm bracelets, will completely revamp the design of its 2,700 shops worldwide, unveil a new logo, increase marketing campaigns featuring celebrities and launch themed collections, including Harry Potter and Walt Disney's Frozen.

Pandora's sales increased more than 10-fold in the decade to 2017 as it found a relatively unoccupied market niche between cheaper accessories found in stores like H&M and more expensive jewellery such as that from Tiffany & Co.

But a lack of innovation and overstretching itself at both the top and bottom end of the market has kept both shoppers and investors at bay recently.

"Customers tell us they used to think of Pandora as affordable but don't any more. The brand has drifted away from its original position and now we're trying to move it back to what made Pandora," Chief Executive Alexander Lacik told Reuters in an interview this week.

"We have to strengthen our position as an affordable jewellery brand big time," he said.

Lacik took the helm at Pandora, which sold 280,000 pieces of jewellery per day in 2018, in April after the former CEO was ousted last year after several profit warnings.

Investors have generally welcomed Pandora's new strategy, which was launched at the beginning of the year and focuses on cost savings, improved brand positioning and less promotions.

Pandora's stock has risen 10 percent since the beginning of the year to 296 Danish crowns ($44.24) a share, still a far cry from a 2016 peak of more than 1,000 crowns.

The firm said it will start using more "influencers" and celebrities to entice young shoppers. The use of Colombian pop singer Shakira to promote jewellery in Latin America had been positive, it has said.

The company will showcase a bigger variety of its jewellery in its stores, allowing shoppers to see and touch the products, while also refreshing the online experience on marketplaces like China's Tmall.

"We hope to drive a much more interesting interaction with the shoppers," said Lacik.

By Jacob Gronholt-Pedersen; Editor: Kirsten Donovan