Traders are furious about the loss of a car park in a multi-million pound development scheme.
Developers Beeleigh want to build a food store on the old gasworks site off Church Road in Hove.
The scheme has already been granted planning permission.
Brighton and Hove City Council, as one of the landowners, is likely to give the scheme the go-ahead at a meeting on Wednesday.
The plan includes demolishing St Andrew's School and building a new one on what is now the Malvern Street car park.
A playing field would be installed on the existing school site.
Keith Bryden, who chairs Hove Business Association, said: "We are concerned about the loss of this car park.
"It will badly affect traders at the northern end of George Street and in Blatchington Road."
Mr Bryden, who runs a do-it-yourself shop in Blatchington Road, said the loss of the car park could put business at the Co-op and Woolworths at risk.
The council said a new public car parking area would be provided at the rear of the store in an accessible position.
It has told Tory councillor Brian Oxley that the store is likely to be operated by Tesco.
It added that Beeleigh would be required to submit a second application to cover details of the scheme before it could go ahead.
Coun Oxley said: "Many people are looking forward to a convenient local supermarket on this site.
"I hope the design and scope of the development will both be consistent with Hove's heritage."
Hove MP Ivor Caplin has backed the plans.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article