Waitrose said on Thursday it plans to treble the size of its online grocery operation to a £1 billion pound business over three years and would build three new automated distribution centres to hit the target.

Waitrose, part of the employee-owned John Lewis Partnership, will end its supply deal with online grocer Ocado in 2020. Ocado is instead partnering with Marks & Spencer.

Waitrose said it would work with Today Development Partners (TDP) to develop three state-of-the-art automated customer fulfilment centres (CFCs).

Its current Waitrose.com service is provided through a combination of deliveries from stores and one distribution centre.

Waitrose said Ben Stimson, currently retail director, has been appointed to the new role of digital director with immediate effect to lead the programme.

Online is Britain’s fastest growing grocery area. Industry researcher IGD expects it to expand by 52 percent over the next five years to £17.3 billion.