A leading retail lobby group has expressed confusion over government lockdown rules that state which shops are essential and what they can sell.
The British Retail Consortium, which represents the industry, said the new guidance creates "arbitrary" lines over what is or is not essential.
A supermarket can, for example, sell "non-essential" homeware if it is stocked on its aisles.
But if the goods are situated on a separate floor, it must close the area.
The guidance was released as England entered a second lockdown, beginning on Thursday, to stop the spread of the coronavirus.
Essential retailers such as supermarkets and food shops are allowed to stay open, while vast swathes of the industry have been forced to close until at least 2 December.
Tom Ironside, director of business and regulations at the BRC, said: "The retail industry has invested hundreds of millions of pounds to make stores safe and secure for customers and we don't believe that any retailers should be required to close.
"The new regulations create arbitrary lines over what is and isn't an 'essential' retailer.
"Unfortunately for many people, this means they cannot visit shops to get the items that are essential to them, from the home office equipment and electronics they need for work, or the pots, pans, fridges and freezers they need during lockdown."
He says the BRC is estimating that closed shops will lose out on £2bn a week and it is essential they be allowed to open - and stay open - from early December.
Click and collect provision
Although the lockdown was announced last Saturday, rules were not released by the government until Thursday.
Retailers in England allowed to trade during lockdown two include food retailers, including specialists such as butchers, off-licences and laundrettes.
Shops that must close include clothing stores, homeware stores and charity shops, although there is provision for click-and-collect orders.
The new rules state that where a retailer has an embedded business operating within its premises - such as an electronics shop within a supermarket - the embedded business must close.
Sainsbury, which owns Argos and has other concessions operating in-store, told the BBC: "We are reviewing the latest government guidance and will keep everyone updated."
Marks and Spencer said it was "fully complying with the legislation and operating our stores in line with the recently published guidance", adding that it had temporarily closed all its 27 standalone clothing and home stores and outlet stores, as well as all 300 of its in-store cafes.
It said that the closure of non-food operations had seen it shut 238 floors, equivalent to half its selling space.
Technology products including laptops and phones are deemed non-essential.
Currys PC World said it was offering order-and-collect at its Currys PC World stores, but was unable to do this at Carphone Warehouse outlets because of "technical limitations".
However, it had a number of support services set up and was offering next-day free delivery on mobile phones.
Retail analyst Neil Saunders, from GlobalData Retail, said is was "totally clueless" and a muddle.
He questioned why non-essential parts should close to limit interactions, but interactions in the essential part didn't matter: "Because, as everyone knows, the virus only spreads in non-food areas.
"If the impact wasn't so serious, this farce would be funny."
But the rules for England should avert some of the confusion seen in Wales, after it put a stop to sales of "non-essential" items. In mixed-use stores, whole aisles and in some cases certain products, such as bedding, were left stocked, but simply taped off.
Baby clothes were only belatedly added to the permitted products list, while one shopper in Cardiff was told period products were not "essential" products and was not allowed to buy them. The Welsh Retail Consortium said shop staff were having to referee in stores.