Rows of black T-shirts at a small stall hang near a banner reading “black shirts 40 baht” – a fraction of the usual price of 200 to 500 baht (US$6 to US$15) – drawing a steady stream of shoppers.

“We sell at this price so all Thais can wear black to pay respect to the queen mother,” said the business’s owner, Thanachote Siripadungdech, who launched the promotion shortly after the palace announced former queen Sirikit’s death.

The royal family holds a central place in Thai society, with portraits of its members seen in homes, offices and public spaces across the country.