The entire nation celebrated His Majesty the King's 79th birthday yesterday when yellow-clad subjects gathered in every province to show their loyalty and to mark the special occasion.

His Majesty yesterday stressed the importance of unity to ensure a stable and prosperous future for Thailand.

Thousands of people waited for Their Majesties the King and Queen's motorcade to pass along Rajdamnoen Avenue in the evening. All loyal subjects wore yellow, some waiting at the site where the evening motorcade passed had been there since the morning in order to get a glimpse of the royal family.

One million candles were distributed yesterday by the December 5 Foundation at Sanam Luang, where tens of thousands congregated in honour of HM the King.

More people came to the area than in previous years, with the waves of humanity, mostly wearing yellow shirts symbolising the King's birth date on a Monday, stretching from Wiset Chaisri Gate at the Grand Palace to Rajdamnoen Nok Avenue.

Some who waited for the royal motorcade cried as they caught the sight of the King in his limousine. When passing his loyal subjects, His Majesty waved to them. The loyal subjects chanted "long live the King" loudly when the car passed.

In the morning, the King and other members of the royal family took part in a royal ceremony and Buddhist and Brahmin rites at the Grand Palace to mark the special occasion.

During the ceremony, HRH Crown Prince Maha Vajiralongkorn wished His Majesty a happy birthday on behalf of the royal family. Prime Minister General Surayud Chulanont then offered best wishes on behalf of the Thai people, followed by Meechai Ruchuphan, president of the National Legislative Assembly.

In turn HM the King replied by saying that Thai citizens should unite for the country's sake.

"Together, Thai people established the nation until it prospered and became stable. This has continued for a long time despite at times the country facing emergencies and trouble," the King said.

"We all surmounted these [odds], however, through wisdom, through dhamma and goodness, and through unity. It enabled us to be free, happy and prosper until today. It should be a reminder for all of us who reside in this land to be united ... and be reasonable and responsible for the public in order to rid the bias and nurture loving kindness and unity," he said.

Sanam Luang and Rajdamnoen Avenue were bright with the light of millions of yellow candles lit at the auspicious time of 7.29pm. Loyal subjects in other provinces also lit candles at the same time.

Thousands of people had lined up at Sanam Sua Pa since early morning to write well-wishing messages to the King.

Elsewhere, the celebrations saw more people wearing yellow shirts than ever before.

In Chiang Mai, a gigantic yellow flying lantern - 13 metres or four-storeys high - and made of 2,200 pieces of yellow paper with the message "Long Live the King" was sent off.

In Mae Hong Son province, refugees from Burma lit candles in honour of the King.

In the north-eastern province of Nakhon Ratchasima, local government officials pledged to be good civil servants.

In Buri Ram, 100 elderly people at an old folks home made an alms offering to monks, and in the violence-torn southern province of Yala, both Buddhist and Islamic rites were performed while blood was donated.

In Bangkok, 580 monks accepted alms by loyal subjects early in the morning yesterday.

Fireworks were set off everywhere in the country to celebrate the day.