Plans for a new Tesco supermarket in a mid Wales town could create more than 300 jobs, says the firm.
Tesco says a 'vibrant' Newtown will be good for business
However, there are fears that the store in Newtown, less than a mile out of the town centre, could have a detrimental effect on its shops.
But the company said planned pedestrian crossings linking it with the town centre would encourage people to shop in both areas.
Tesco wants to develop a livestock market derelict since 2001.
The company has also recently received permission to build a store in Llandrindod Wells, where it is to create 167 jobs.
Mayor Elizabeth Sheriff said: "The jobs would be great for the town - we need the employment - but some shopkeepers are concerned that people will shop under one roof at Tesco.
"Elderly people walk into town to shop and if some shops close as a result of Tesco it will be difficult for pensioners. We would all like to shop at Tesco, but there are many other things to consider."
Peter Jacks, a butcher for 30 years who owns a shop in Newtown's market street, said the supermarket would have a negative effect on the town centre.
"I don't really want Tesco's here because it won't be good for town centre shops such as mine," he said.
Newtown is already home to a Morrisons supermarket and Mr Jacks said that development had had an impact on the town centre.
"In my opinion, fruit and veg and meat is better in the shops, but the convenience of having everything under one roof will be popular," he added.
Tesco said: "It'll be good for business to have a vibrant Newtown.
"The store will encourage linked trips with existing town centre shops.
"We are committed to consulting on these plans so local people can tell us what they think of our proposals and plans for a public exhibition next month will be announced soon."