Thailand's King Bhumibol Adulyadej, the world's longest-reigning monarch, marked his 80th birthday Wednesday with a warning that political disunity can lead to disaster in his country. Thailand is moving to heal political wounds this month with elections that are to return it to democratic rule following a military coup last year. VOA's Luis Ramirez reports from Bangkok.

King Bhumibol Adulyadej, born 80 years ago Wednesday in the U.S. state of Massachusetts, is universally adored in Thailand. Thais see him as a symbol of national identity, unity and stability in a country that has had at least 18 coups d'etat since 1932, when Thailand made a peaceful transition from an absolute to a constitutional monarchy.

The latest coup, which ousted then-Prime Minister Thaksin Shinawatra in September of last year, was the result of public anger over corruption - and over what some here saw as Mr. Thaksin's disrespect of the king.

Debate over the validity of the coup has pitted members of Thailand's middle class, who resented Mr. Thaksin's style and personality, against the working class, who support the former prime minister.

Thailand hopes to heal those political wounds, and Thai voters will cast ballots on December 23 to put a democratic government back in place. Mr. Thaksin's Thai Rak Thai Party was forced to disband, but his supporters have been regrouping and campaigning as members of new parties, and some analysts expect the poll to be contentious.

In a one-hour address to the nation late Tuesday, the king issued a call for unity - a recurring theme of his recent speeches.

He says Thailand's military and civilians must be united, like two legs that have to walk in unison, with one leg stepping forward while the other waits behind. He says that if Thais are not united, the country will - in his words - face disaster.

For Thais, the monarch's advice this year has special meaning, as his age and failing health have become evident. The king, who took the throne in 1946, was recently hospitalized for three weeks after suffering symptoms of a stroke and other problems, and in public appearances, he appears frail.

Talking about the monarch's passing and the future of Thailand without him is considered impolite here, but the unspoken preoccupation is evident among the thousands who gathered outside the palace in the pre-dawn hours of his birthday, wearing yellow or pink - colors that have come to symbolize the monarch.

Pornphan, a public sector employee who traveled here from northern Thailand for the occasion, arrived outside the palace at five in the morning to wait for a glimpse of His Majesty. She says Thailand has him to thank for its overall stability and growth in the decades of his rule.

She says the king has been a force of love and unity for the benefit of everyone in the country.

Next in line for the throne is 55-year-old Crown Prince Maha Vajiralongkorn, who is not as personally popular as his revered father.