Shopkeepers in Thailand selling royal memorabilia and portraits are reported to be struggling to meet the unprecedented demand for pictures of late King Bhumibol Adulyadej, as 67 million Thais continue to mourn a week after his death.

The ninth king of Thailand's 234-year-old Chakri Dynasty died on 13 October at the age of 88. He was the longest reigning monarch in the world and was revered for leading the country through its turbulent times.

Business is soaring and busy, especially in Dinso road, located close to the Grand Palace, where the king's remains are reported to be kept for about a year until a royal cremation is held. The road is believed to be known famously as "portrait street" and sells even gold-framed portraits of the king.

"Business has increased about 70 to 80 percent," Reuters quoted Charlie Wangthamrongwit, a shop keeper in Dinso Road as saying. "We just can't meet demand. Everything king-related is in demand now," the shopkeeper added.

The 62-year-old said the standing portrait of the king was the most popular, as shoppers queued in front of his shop not minding the sweltering heat.

Portraits of the king's son and successor, Crown Prince Vajiralongkorn, are also reported to have increased, although some shopkeepers have said they have not received any orders yet.

"Nobody has ordered the prince's portrait yet. Right now we are in a period of mourning," Charlie said.

On Monday (17 October), some parts of Bangkok were decorated in black and white funeral bunting. Even the portrait of the king was framed with black cloth, and the government is not planning to remove any of the portraits now, a spokesman told Reuters.

Besides, Thais are being instructed on how to rearrange the portraits correctly as phrases like 'Long lives the king' no longer apply.

Earlier, black cloth was reported to have been in huge demand in the country, where many Thais dressed in the colour to mourn the king. The government had to intervene as the surge in demand had led to several retailers hiking the price. Deputy Prime Minister Somkid Jatusripitak eventually asked the garment manufacturers association to increase production of black clothing.

Some Thais, with gas burners heating black dye, were even reported to have volunteered to offer free dyeing services near the palace.