Waitrose said this week it had ruled out a move into Northern Ireland.

Nigel Keen, director of development at Waitrose, said the retailer had looked at opening in the province - the only part of the UK it does not have a presence - but had decided to focus instead on England.

"We are still a very immature business in England," said Keen. "Sixty per cent of our target customers don't have access to a Waitrose and we want to concentrate our efforts on growth in the north and south west."

Keen also said the supply chain in Northern Ireland presented "a real challenge", which had also deterred the company from setting up shop there.

This week Waitrose opened two more stores in England - in Harborne, Birmingham, and in Cheadle Hume - marking its first foray into Greater Manchester.