Business minister Michael Fallon and his Labour shadow Chuka Umunna have issued a rallying call to c-store retailers to play their part in making Small Business Saturday a success on 7 December.

The UK’s first Small Business Saturday, which was spearheaded by Umunna but enjoys cross-party support, is based on an initiative started in the USA three years ago.

Speaking at the Association of Convenience Store’s Heart of the Community event on Tuesday, Umunna urged local shops to get involved.

“Small Business Saturday is set to be the biggest celebration of small business this country has ever seen,” the shadow minister added.

Also speaking at the event, Fallon said Small Business Saturday was a great opportunity for everyone to get behind small shops.

Support is growing for the initiative, with 27 local authorities having agreed to offer free parking on 7 December. However, some are refusing to lend support. Weston super-Mare Spar retailer Mark Canniford tried to use his influence as a councillor to persuade North Somerset Council to waive parking charges for the day, but to no avail.

“It’s disappointing to have a local authority which claims to be pro-business but does nothing to show that it is,” he said.

Conwy council in North Wales is supporting the event by running a prize draw in a local paper. Spar retailer Mike Skerrett gave a £50 voucher after the council offered him the chance to take part.

Edinburgh Premier retailer Linda Williams is planning an array of activity on the Thursday, Friday and Saturday.

“We are really hoping the initiative’s success in the USA will be replicated here,” she said.

The event has the backing of American Express, which has launched a national ad campaign and a special offer for 7 December. Cardholders will get £5 back when they spend £10 or more at a participating business on the day.