"Shortbread is America's second favourite cookie, after chocolate chip," says Anne Robinson, owner of Scottish Gourmet USA, a small business in North Carolina. She imports Scottish produce and sells it at her store in Greensboro and online.

"But how much will consumers pay for their little pleasures?"

Along with Andrew Hamilton, her Scottish husband, she's about to find out. They are putting up prices, partly due to the 10% tariff on imports into the US from Scotland.

There are other reasons, including the weakened US dollar against the British pound, higher healthcare costs for her employees and higher employer costs for her suppliers of "bangers, bacon, pies, tablet, kippers, bannocks, cheese, shortbread, fudge, mugs and more".

"We sell the luxury brands of shortbread, along with Walker's, the world's biggest maker of shortbread," Anne says.