New research has outlined "the damage that will be done to Scottish shop workers if the SNP do not vote against the Government on plans to devolve Sunday trading powers to England and Wales" on 9 March.
The report, produced by Edinburgh-based economic consultancy Biggar Economics, claims the Scottish workforce will lose £74m a year as a result of Sunday trading changes south of the border with each Scottish worker losing around £1,300 a year.
The report states that if Sunday pay premiums for Scottish workers were to end as a result of Sunday trading devolution in England and Wales, over 60,000 retail employees would be affected. There would also be a significant effect on the Scottish economy, with reduced economic output of £71m and a total household income reduction of £87m.
The Scottish National Party have said that they are yet to commit to which way they are planning to vote on the issue next week, despite claiming that they would vote against the measures to protect Scottish workers when the plans were first raised in November.
There have been suggestions that the Party was prepared to drop its opposition to the plans.
A Keep Sunday Special Campaign representative said: "Whatever deal the SNP may be looking to strike with the Tories, it is difficult to see how it would protect Scottish workers from losing their premium pay. It is these Scottish workers and families that will suffer as a result of the plans to devolve Sunday trading hours, and the SNP must stand up for them and vote against the measure next week."
The Government’s Sunday trading proposals could have 30 Conservative MPs including two ministers planning to vote against the plans in the Enterprise Bill next week, though the Bill is still expected to go through.
Communities minister Brandon Lewis said: "If you stop to think about it the idea of shopping hours being determined by central government is ridiculous." Contrasting the retail experience of people in 1994 when the present laws came into force and now, when online shopping is available 24 hours a day, Lewis said "we need to reform these laws."
One of the ministers considering their position over the issue said: "I worry that people who don't have an option over their job, because it's the only job they've got and want to spend time with their families, are going to find that difficult".
Compromises being offered to stave off the rebellion, include changing the rules "only in zones needing an economic boost such as high streets".
Another amendment to the bill has been put forward by former cabinet minister Caroline Spelman, which would allow "cities with large numbers of tourists" to opt-out of Sunday trading laws.