A MILITARY court in Thailand has sentenced a web editor to four and a half years in jail for publishing an article five years ago which was ruled as defamatory to the nation's king.

The punishment is the latest manifestation of an intensified crackdown on alleged criticism of the monarchy that has been waged by authorities since the army seized power in a May 22 coup.

Thailand's lese majeste law is considered the harshest in the world, with those accused of defaming, insulting or threatening the monarchy facing jail terms ranging from three to 15 years.

The sentence against Nut Rungwong was halved because he pleaded guilty to the charge, according to an official in the army Judge Advocate General's department.

Rungwong edited the Thai E-News website, which is now blocked by censors. The article was written by academic Giles Ji Ungpakorn who fled to Britain.