Bangkok: Thai authorities have banned a five-month-old French edition of Marie Claire magazine because of an article which police said defamed the kingdom's royal family.
Thailand's royal defamation laws are among the world's harshest and can land offenders decades behind bars.
An official order, published in the Royal Gazette late on Friday and signed by national police chief Chaktip Chaijinda, outlawed importing or distributing the November 2015 issue of the magazine printed in France.
"Also, any magazines [of that edition] will be confiscated or destroyed," it added.
A Thai police spokesman declined to comment on the order, which cited a 2007 publishing act that grants the national police chief power to ban any printed material that defames the monarchy or affects national security.
The reason for the delay in outlawing the edition was not immediately clear.
However the magzine would not have been widely on sale in the kingdom.
Prosecutions under royal defamation laws have surged since royalist generals seized power in a 2014 military coup, with many Thais facing jail time for social media postings on the monarchy.
The outlawed Marie Claire magazine carried a French-language article critical of Thailand's Crown Prince Maha Vajiralongkorn, who is next in line to the throne but does not enjoy the widespread adulation of his 88-year-old father, who is ailing.
The monarchy has become an increasingly sensitive topic as hospital-bound King Bhumibol Adulyadej, the world's longest reigning monarch, enters his twilight years.
Media in Thailand routinely self-censor when reporting on palace affairs to avoid falling foul of kingdom's lese majeste law, which carries a 15 year jail sentence per offence and is broadly-interpreted by authorities.
Last year a local Thai printer removed several New York Times articles that touched on the monarchy, forcing the paper to carry blank spaces.
The Economist has also seen editions of its magazine banned in Thailand for carrying sensitive stories on the royal family.