The Chancellor is expected to announce plans in the Budget tomorrow to allow local authorities to relax laws which prevent big stores from opening for more than six hours.
Speaking to Premier, John Ashcroft from the Keep Sunday Special, said: "So the weekends in general and Sunday's in particular are times for the family to be together, it's an important asset for strengthening family life."
He argued there was no economic reason to extent opening hours: "I think the idea that people have money burning a hole in their pockets which they simply don't have time to spend, is completely out of touch.
"Household budgets are under pressure, people haven't got more money to spend."
CARE CEO Nola Leach said: "Family life should not be sacrificed on the altar of profit.
"Britain can only win the global race if we pace ourselves and that's why the principal of time off in common, where families can spend time together is so vital.
"Extending trading hours on a Sunday in our view is an extraordinarily short sighted policy that will place even greater strains on our society's fragile social fabric.
"Family breakdown already costs the Exchequer in the region of £46billion a year, £34billion more than the savings the Chancellor wants to make by cutting the welfare budget.
"We are deeply concerned about the consequences these proposals could have on the social environment of British society.
"Quality of life and personal wellbeing will suffer if these proposals are adopted and therefore we would strong warn against any attempt to extend Sunday trading laws."
Listen to Premier's Hannah Tooley speak to John Ashcroft here: