“How are you spelling that? Pee... Gee... Tips?” asks Renika, a cashier at the WholeFoods store on 7th and 24th Street in Manhattan.

“I don't know it but if it's special tea, it will be near the 'erbal teas at the back of the store,” she adds.

Opposite the yoga mats and soy blend scented candles, and hidden between packets of echinacea and loose leaved apple Rooibos, are 12 boxes of a more familiar friend — PG Tips pyramid teabags, selling at $6.99 for 40.

While expats have been able to buy PG Tips for years in New York from a handful of twee specialist English food stores, ordinary supermarkets will now stock Britain's biggest selling tea brand across America, thanks to a marketing deal between Unilever and World Finer Foods, a New Jersey-based food distributor.

“England's #1 Black Tea comes to America. Wake up America! If you never understood the British obsession with tea, now's your chance to find out what all the fuss is about” gushes the advert.

Americans have not always welcomed English tea with open arms. Unilever may well hope that the tea crates shipped from its Kenyan Brooke Bond plantation to the East Coast of America will get a different reception from one received in 1773, when the Boston Tea Party prompted the American Revolution.

Two centuries on, and English tea is no longer seen as a symbol of oppression, but as an aid to health.

The American specialty tea market has almost quadrupled in 15 years and, according to the US Tea Association, based in New York, is now worth $6.8billion (£3.4billion) a year.

Joe Simrany, president of the association, points out that “Americans never used to even think about tea. It was the drink consumed by old women. There were no young people involved in the industry. Thirty years ago we either drank coffee or iced tea and consumed 60 gallons per head per year of soft drinks, much to our detriment.”

He added that America's health drive over the past two decades has triggered a boom in the specialty teas, credited with lower caffeine levels and antioxidants. Unilever's other big tea brand, Lipton, occupies more than half of the US tea market, followed by Tetley, Bigelow, and Reily, the New Orleans iced tea specialist.

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