(Sharecast News) - Aldi announced a record £800m investment to accelerate its expansion in Britain, following its strongest-ever sales performance.

The privately-owned German discount supermarket giant said the investment would support the opening of 23 new stores in the next 16 weeks, including locations in Muswell Hill, London, and Caterham, Surrey.

It would be part of a broader £1.4bn, two-year plan that would include refurbishing 100 existing stores, expanding distribution centres, and upgrading technology infrastructure to sustain growth.

Aldi said its commitment to affordability was central to its strategy, as it had cut prices on over 300 products in the last three months.

The supermarket, the self-proclaimed UK's cheapest, said it had maintained its lead in price comparisons, outperforming traditional competitors by 14%, according to Which.

Aldi's investment announcement came alongside its latest financial results for the 12 months ended last December.

It said sales surged by £2.4bn, reaching £17.9bn - a 16% increase from the prior year.

The company's pre-tax profits also jumped to £536.7m, driven by record sales and improved operational efficiencies.

Aldi said its operating profit rose to £552.9m, with a profit margin of 3.1%.

In addition to growth in store numbers, Aldi said it had strengthened its relationships with British suppliers, spending an additional £1.3bn with its 5,000 partners last year.

That included a £750m deal with Kent-based AC Goatham & Son to establish the first 'Aldi Orchard' on a 200-acre farm in Gravesend.

Aldi also made significant investments in its workforce, with £79m spent on pay increases this year.

The company said store assistants' wages were raised to £12.40 per hour, and £13.65 for those within the M25, making Aldi the sector's highest-paying employer.

With a current market share of 10%, Aldi said its continued expansion and focus on affordability were set to attract more shoppers across the UK.

"British shoppers are voting with their feet and choosing Aldi as their first-choice supermarket - we're responding with our biggest ever annual investment in Britain," said Giles Hurley, chief executive officer of Aldi UK & Ireland.

"For every £1 of profit generated last year, we're investing £2 this year - opening more stores and building the supply infrastructure to bring high-quality, affordable groceries to millions more families the length and breadth of Britain.

"We're also investing at record levels to cut prices, reward our amazing colleagues and support more causes in our local communities."

Hurley added that the company was creating "thousands more jobs" and more opportunities for its growing base of British suppliers and farmers.

"As we head towards the Christmas trading period, we're all set to launch our biggest and best-ever seasonal range, including hundreds of premium range products at unbeatable prices for our customers."

Reporting by Josh White for Sharecast.com.