UK tourists in Thailand told to 'behave respectfully' and wear 'sombre' clothing after death of the king

British tourists in Thailand have been advised to "behave respectfully" and wear "sombre" clothing as the country begins a year-long period of morning after the death of King Bhumibol Adulyadej.

Thailand began its first day in 70 years without a king on Friday in a profound state of mourning, after the king passed away peacefully on Thursday at Bangkok's Siriraj Hospital.

The 88-year-old monarch became king in 1946 and was revered in Thailand as a demigod. He anchored the South-east Asian country through violent upheavals at home and communist revolutions next door, as well as a period of rapid development.

Around one million visits by British nationals are made each year to Thailand and in the wake of the king's death, the UK’s Foreign and Commonwealth Office (FCO) has urged British tourists to “respect the feelings and sensitivities of the Thai people."

A statement released by the FCO said "Access to entertainment, including restaurants, bars, and shopping areas may be restricted and you should behave respectfully when in public areas.

"If possible, wear sombre and respectful clothing when in public. Check local media regularly and follow the advice of the local authorities."

Australia’s foreign ministry has told tourists to “refrain from any behaviour that may be interpreted as festive, disrespectful or disorderly" and warned there may be disruption of commercial and public services.

Western diplomats in Bangkok advised tourists and expatriates to wear black and respect the mourning period in Thailand, the Sydney Morning Herald reports.

Thailand’s Prime Minister Prayuth Chan-ocha said “all entertainment functions must tone it down for 30 days”.

In Bangkok, residents began lining the streets where the king's body was expected to pass on Friday afternoon in a royal procession from Siriraj Hospital to the Temple of the Emerald Buddha, or Wat Phra Kaew, which is located on the grounds of the ornate Grand Palace.

Television channels were running non-stop footage devoted to the life of the king, who was deeply revered and held up as a unifying figure in the politically fractious country despite two coups in the last decade alone.

Most Thais have seen no other king in their lifetime and thought of Bhumibol as their father and the embodiment of goodness and godliness.

"It is a great loss for Thai people," said Siwanart Phra-Anan, on office worker in the financial district. "His Majesty will be in Thai people's hearts forever."

Thailand has some of the world's strictest lese majeste laws, which can result in a 15-year prison sentence for anyone who defames, insults or threatens a member of the royal family, the BBC reports.

King Bhumibol's son and heir, the 63-year old Crown Prince Maha Vajiralongkorn, has been announced as the new monarch in accordance with the constitution, however he has asked for more time before ascending the throne following the death of his father and world's longest-serving monarch.

Additional reporting by agencies