High street shops in jeopardy 'if larger premises are taxed'
The organisation has said that nearly 40% of the extra tax, aimed at generating revenue to support town centres, could in fact damage the urban area that the policy is designed to help.
The BRC this week launched its Manifesto for Retail in Northern Ireland 2011, which urges the Assembly not to penalise the retail sector so it can best contribute to Northern Ireland's economic recovery and create more jobs.
Retail is the UK's largest private sector employer with 9% of the Northern Ireland workforce, around 73,500 people, working in the sector.
The BRC argues that businesses operating on narrow margins will not be able to expand their workforce if a tax affects the viability of individual stores.
The Belfast Telegraph has already highlighted the mounting challenges facing the high street - including proposed parking charges, high rates and out of town shopping developments poaching customers.
Earlier this week the BRC revealed the biggest sales drop in its history, with total sales in March down 1.9% on a year ago.
Director general of the BRC, Stephen Robertson, said that retail is "not a piggybank to be broken into" when the Executive needs some extra cash.
"The retail sector will deliver far more for Northern Ireland if it is supported and helped to grow, bringing in investment and creating jobs," he said.
"With retail sales falling by 1.9% in March compared with a year ago, retail margins are already under severe pressure.
"This proposed tax on large retailers is contradictory. It's supposed to provide support for town centres, but up to 40% of it could be paid by the flagship stores that help make town centres such attractive shopping destinations.
"It's supposed to bring in extra funds for the Executive, but risks destroying the bigger economic gains that would come from retail growth and job creation.
"Support for our high streets is vital."