AMMAN: Jordan's king has endorsed a controversial new media law that critics say could severely stifle online expression.

The law requires 400 news websites operated by Jordanians to register with the government and obtain licenses. It also gives authorities the power to block and censor the sites, and holds publishers and editors liable for posted comments.

The official Petra news agency says the law was endorsed late Monday by royal decree.

An international rights watchdog has deplored the move, saying the legislation would make website managers share the responsibility for posted comments.

Human Rights Watch says that asking website owners to check online comments is "not a valid" demand and such extensive vetting would not be "feasible."

The New York-based group has suggested removing libelous comments as an alternative remedy.