Wide-scale discounts failed to prevent sales falling in November as official figures added to signs of a tough Christmas.
Sales volumes fell 0.4% from the previous month, according to the Office for National Statistics (ONS), with poor sales of computers, watches, jewellery and carpets.
The fall in sales, despite a large number of special offers from retailers desperate to drum up trade, was bigger than the City had expected and brought to an end two months of growth.
Non-food retailers battled against their biggest monthly fall in sales since February, while food stores saw their largest fall for half a year.
This was despite strong internet demand and a recovery in clothes sales.
However, there was some good news for cash-strapped households as the figures suggested that average prices declined 0.2% on the previous month.
The retail sector has fallen victim to a far-reaching consumer spending squeeze, driven by high inflation, muted wage growth and weak confidence. Major players including Mothercare, HMV and Carpetright have all suffered, with only a few, such as Sports Direct bucking the trend.
There are fears that big name retailers could go under after Christmas as consumers rein back spending amid fears of a recession.
In Belfast a partnership initiative has been launched to attract more visitors to the city centre.
Free on-street parking from 4.30pm on weekdays and all day Saturday has been negotiated right up until Christmas between Belfast Chamber of Trade and Commerce and Roads Service.
A £250,000 Christmas advertising campaign launched by Belfast Visitor and Convention Bureau also highlights Christmas shopping and entertainment experiences available " ... only in Belfast".
BVCB's chief executive Gerry Lennon said: "Collectively, BVCB, BCTC and our partner agencies represent over 1,000 businesses within the city and there are already strong indications that Christmas is gaining positive momentum in Belfast.
"The strategic and operational activities shown here are real evidence that Belfast is working together with the primary aim of driving a bumper Christmas trade to the city.
"The free parking initiative is an excellent example of joint public private partnership. We're receiving positive feedback already from our member businesses and we hope to see this continue right through to the New Year."
Victoria Square and Castle Court shopping centres, sports retailer SS Moore and Lunn's Jewellers have all reported brisk sales this month.