O'Brien's Sandwich Bars plans to enter the highly competitive London market with an aggressive 18-month expansion programme.

Company founder and chief executive Mr Brody Sweeney says the group hopes to open 50 outlets in and around the British capital, going head-to-head with more established groups.

"We will be competing with Prêt à Manger, which has about 100 outlets, among others," he said. "They are a good operation but we make our products to order whereas they sell prepacked goods, like Marks & Spencer. We think that sets us apart from our competition."

Competition in the £3.5 billion (€5.1 billion) UK sandwich market is intense with everyone from supermarkets to pubs and dedicated outlets to garages vying for a slice of the action.

O'Brien's currently has 120 stores in the UK but these have been predominantly outside the populous London and the south-east regions. Mr Sweeney said high rents had kept O'Brien's outside the London area to date, but the group reckons these have now fallen to a level where it will be possible to roll out a profitable franchise operation.

He noted London had proven a difficult market for sandwich and coffee outlets. Prêt à Manger, founded three years before O'Brien's, has struggled to retain its momentum and recorded a £20 million loss last year, although its British operation did manage a £6 million profit.