At Shepherd's Bush market in London, a greengrocer is flirting with the law.

It is selling potatoes by the pound and onions by the ounce.

"It's just easier to understand," owner Sylvia Fletcher explains.

"People here don't realise how much they're getting for a kilo."

Under current laws, businesses can put imperial units on their signs, so long as prices are also clearly displayed in metric, but at this stall there are few signs of kilos or grams.

Customers claim they prefer the system of measurement that originated in the old British Empire.

"We're being integrated to work alongside everybody else, but I think we should go back to the old ways to be honest," staff member Sam Barlett said.

A few miles away, at one of the world's oldest wine shops, the sentiment is similar.

Simon Berry, from Berry Brothers & Rudd claimed the "Brussels bureaucrats" of the European Union had thwarted his dreams of selling champagne in a pint bottle.

"It's the perfect size for sharing," he exclaimed.

"But I could, quite literally, be arrested for selling an imperial pint of champagne".

Pounds and ounces are part of the United Kingdom's history

Although steps towards metrification in Britain began before the country entered the European common market, the gradual movement across the continent towards a French system has become a symbol of EU-led integration.

Fans of imperial units claim Brexit has breathed new life into their campaign.

Road signs still use miles, due to a legal exemption. ( Wikipedia: Starvos1 )

"We're not saying abolish the metric system," said Warwick Cairns from the British Weights and Measures Association.

"We think if people want to use the metric system we think that's absolutely fine.

"Similarly, if people want to use pounds and ounces, pints and miles then they should be allowed to do so."

Beer can already be poured in pints and road signs are in miles, due to a legal exemption.

Mr Cairns said his group had "long been on the wrong side of history", but claimed "a large number" of Brits who want to use imperial units have contacted him since the EU referendum.

"We just want the freedom to choose how we weigh things," he said.

"The imperial system is part of our culture. People like to protect languages, why not measurement systems?"

Turning back the clock not worth it

Of course, there are plenty of people, perhaps even a majority, who think the imperial system should be allowed to die out.

Among them are consumer lobby groups and businesses reliant on trade with Europe.

London butcher Russell Aqeel said only elderly customers asked for meat in pounds and ounces and he did not think the imperial system was really worth fighting for.

"Things work pretty well as they are now and all the younger generation only know metric," he said.

The debate may seem laughable to some and, obviously, it is not the first order of business as Britain begins to work its way out of the EU.

But in the wake of the historic referendum, there has been a push for the country to "take back control" of everything from fruit measurements to foreign policy.

In many ways, pounds and ounces seem a tiny part of a much broader debate about Britain's new identity.