The ban on click and collect services is affecting small and local businesses, Retail Excellence has warned.
The Government announced during the week that click and collect for non-essential retailers is prohibited under new restrictions.
Non-essential shops, which closed their doors on New Year's Eve, were instructed that they would only be permitted to operate delivery services moving forward.
Duncan Graham, Managing Director of Retail Excellence, said click and collect was a lifeline for smaller retailers.
He told Down to Business with Bobby Kerr that it has been an "emotional, operational and financial rollercoaster" of a year for businesses.
Mr Graham said the summer had been "quite buoyant" for retailers, with sales bouncing back after the initial lockdown.
"It was a particularly difficult time going into the last lockdown," he added.
"Christmas actually started out really well, December was a good month up until the final few days running up to Christmas."
He explained that the ban on click and collect services "absolutely" disproportionally affected smaller retailers.
Mr Graham said: "If you look at the major multinationals and the larger retailers, they tend to flip to an online platform pretty easily.
"They've got delivery mechanisms in place and it's not a major issue for them.
"But if you look at particularly what was happening in November with the smaller retailers, click and collect was a real lifeline for them.
Since the restrictions have been imposed, smaller businesses now have to source delivery companies, which can be quite difficult, he said, with costs "inevitably" passed on to the consumer.
"It's just really uncertain at the moment and we'll wait and see what happens," he added.