Thai king misses birthday speech

King Bhumibol is the world's longest-serving monarch

Thailand's King Bhumibol Adulyadej has not been able to give his traditional speech to the nation on the eve of his 81st birthday.

Crown Prince Varjiralongkorn went on the radio instead to say his father was a "little sick".

Thais had been looking forward to hearing from their much-loved monarch, who has long been looked to for guidance in times of turmoil.

Thailand is in the middle of a long-running political stand-off.

The international airport was taken over by anti-government protesters for most of the past week, and the situation is only now getting back to normal.

But correspondents say there is still a huge backlog of tourists waiting to leave Thailand.

'Not serious'

Prince Vajiralongkorn informed Thais that the king was unable to deliver the speech "because he was a little sick".

Princess Maha Chakri Sirindhorn, the king's daughter, added that his condition was "not serious", saying he had "a blockage in his throat and a poor appetite".

The king's speech is usually given in front of senior government officials and other specially invited guests on the evening before his birthday.

It is also broadcast live on national radio to his many millions of adoring subjects.

This is the first time in his 62 year reign that the king - the longest-serving monarch in the world - has failed to give the address.

"The king has said to thank [you] for the wishes given out of loyalty," said Prince Vajiralongkorn.