BANGKOK - THAILAND, which just ended a five-month ban on the video-sharing site YouTube, now wants to block clips that accuse a top royal adviser of masterminding last year's coup, an official said on Saturday.

'The video clips pose a threat to our national security,' said Yanaphon Youngyuen, head of the justice ministry's cyber-crime department.

The two video clips, narrated in Thai with English subtitles, accuse General Prem Tinsulanonda, 87-year-old adviser to the widely respected King Bhumibol Adulyadej, of masterminding the coup in Sept 2006.

He has denied orchestrating the takeover.

Mr Yanaphon said the government would only block the two video clips, not the entire site.

Thailand's army-backed government, which came to power after the putsch, banned YouTube in early April after an anonymous user posted a clip showing digitally-altered images of the king next to a photograph of feet.

Thais believe feet are the lowest and dirtiest part of the body, and avoid ever showing their soles in public. Placing feet next to someone's head is seen as a massive insult.

The government lifted the ban at the end of August after YouTube installed filters to stop viewers here seeing clips deemed offensive to the 79-year-old king. -- AFP