The legal action aims to halt proposals to allow shops including garden centres to open for longer on Sundays.
Keep Sunday Special has told Government it plans a Judicial Review on the proposals to allow councils to allow shops to open longer on Sundays, citing that the Government used outdated evidence for the review and has not published an assessment of its impact on family life.
Keep Sunday Special said: "We do not enter into this action lightly, and do so with a heavy heart.
"There are fundamental flaws in the process that the Government has taken and full consideration is needed, not the inadequate process that has taken place to date."
Association of Convenience Stores chief executive James Lowman said: "Longer opening hours will serve only to benefit out of town stores, whilst hurting high streets, Post Offices and small shops – resulting in a net loss of jobs to the economy.
"We fully support this legal action to hold Government to account for their actions."
A Government spokesman said: "Extending Sunday shopping hours has the potential to help businesses and high streets better compete as our shopping habits change.
"The rights of shop workers are key to making these changes work in everyone’s interests. We are protecting those who do not wish to work Sundays, and those who do not want to work more than their normal Sunday working hours."
Anti-Sunday trading issues raised:
- Evidence that does not fit the government’s agenda has been ignored.
- The government has failed to publish the number of responses to the consultation that supported and opposed their proposals.
- The evidence that has been quoted is irrelevant and outdated. Most recently, the Government used evidence from 1970’s Sweden to justify its decision.
- The consultation amounts to an advocacy document for the proposals instead of being a balanced account of the views expressed by respondents to the consultation, suggesting that the government had made it decision on this policy before considering consultation responses.
- The impact assessments have not been published, including the assessment of the Government’s proposals under the Prime Minister’s own family test