The credit squeeze has distracted attention from a far more insidious threat to our island way of life: a looming shortage of curry. Curry houses, institutions as quintessentially British as pyjamas, bungalows and polo, are drifting into decline. Politics, commodity prices and demographic change are threatening our patrimony of over 10,000 chicken tikka palaces. But there is still time to soften the blow, if not avert it.

Spicy food from the subcontinent has been inducing cathartic perspiration and satiety in the British masses since the 1960s. In common with corner shops, curry restaurants provided a commercial and cultural interface between newly arrived south Asian immigrants and the host population. Britons, tiring of such austerity fare as bully beef and dried egg, were ready for a gastronomic adventure. The local Taj Mahal, with its twangy sitar music and flock wallpaper, gave it to them.

An informal national franchise was born. Its workforce of 80,000 and annual sales of £3.5bn place it among the UK's biggest industries. But it is grim among the chutney stands and tandoori ovens. "We are losing a significant number of our curry restaurants," said Enam Ali, chairman of the Guild of Bangladeshi Restaurateurs. "I expect that 10 to 12 per cent of [them] will close in the next few years." The British Hospitality Association said it was "extremely concerned" about the sector. Last Friday, Scottish curry house owners demonstrated outside Holyrood.

The trigger was a new immigration system that will have the unintended consequence of excluding many skilled curry chefs. The government is introducing the regime to atone for its shambolic mismanagement of immigration in recent years. The system also aims to promote English, in a reaction against multiculturalism.

The problem for restaurateurs is that most of their new chefs come to the UK on sponsored visas from Bangladesh. That has been tougher since 2006, they say, and will get tougher still when the new system takes effect in November. It will count for naught that a would-be immigrant can mix a mean masala. He will need fluent English and a high-level cooking certificate too.

The government has suggested that curry houses should employ east Europeans, who need no such qualifications. "We tried that, but it didn't work," said restaurateur Abdul Latif, glumly watching his depleted kitchen staff at work at his Black Country establishment. He added: "We had an east European sous chef, but his chapattis were wiggly at the edges, like maps of Russia." In addition, it transpired that east European economic migrants spoke a different variety of broken English to Bangladeshi ones.

Previously, south Asian restaurants could hire chefs weaned on curry who had come from Commonwealth countries whose soldiers fought for Britain in two world wars. Now they must recruit cooks specialising in dumplings and pickled cabbage from the former Soviet bloc. That is idiotic. But that is the European Union.

Commodity prices are another problem. Rice prices have almost doubled as the result of poor harvests, urbanisation and rampant demand from China and India. The cost of chicken, ghee and spices has also shot up. Curry houses are impeded from passing on these increases by costs of about £2,000 for printing new menus. Besides, affordability has always been a key selling point of curry.

Mr Latif has not increased his prices for four years. He plans to retire next year, aged just 57. He is not making any money, so what is the point of continuing? Similarly, Bajloor Rashid, proprietor of Zarin, a restaurant in Ashford, Kent, has seen weekly takings shrink from £12,000 to £7,000. "We are at the end of our tether," he said.

My feeling is that recruitment problems and high food prices are just contributors to a broader malaise. There are many outstanding curry restaurants, but the collective brand is tired and losing market share. And because it belongs to everyone and no one, there can be no systematic investment to revive it. Moreover, restaurant proprietors such as Mr Latif, who came to Britain in the 1960s and 1970s, are getting on. Their children are rarely keen to succeed them. These offspring are often prospering in the professions, untroubled by capital risk, consumer whims and drunks who solicit service by snapping their fingers.

The slow decline of the curry industrial complex will accelerate at an uncomfortable pace, however, unless the government modifies its plans for immigration controls. It has already exempted from the requirement to speak fluent English those investors who bring £1m into the country. Chefs who are handy with the cardamom should be granted a similar waiver for fixed-term stays. If need be, they can have time off to wrestle with English at night school.

Mr Rashid, who is president of the Bangladeshi Caterers Association, has suggested a scheme along these very lines to Liam Byrne. "The [immigration] minister approved of our formula but didn't do anything about it," said Mr Rashid, who has learnt an important lesson in the ways of politicians.

Mr Byrne should take more serious heed of Mr Rashid. The minister is an MP for Birmingham, where Asian food is produced and consumed in large quantities. Rows of boarded-up balti restaurants would damage his approval rating among voters there. I would be happy to broker a meeting. We could do it over a curry.

jonathan.guthrie@ft.com

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