AMMAN, Jordan — The Jordanian government has blocked local access to about 300 news Web sites under a new law that the sites’ editors and international journalism experts have derided as dangerous censorship aimed at quelling criticism of King Abdullah II.

The law, enacted in September as the opposition to King Abdullah grew more outspoken, requires news sites in the country to register with the government, pay $1,400 in licensing fees and hire unionized journalists as editors, steps that the site operators say they cannot afford. The law also makes editors legally responsible not only for the content of articles they publish, but also for comments posted by readers, many of them anonymous.

“Actions in the past and now clearly demonstrate that they do not believe in press freedom,” Nidal Mansour, head of the Center for Defending Freedom of Journalists, said of Jordan’s leaders. “It’s a global world, and Jordanians should have the right to access Web sites that people in the rest of the world already do.”

Hundreds of news sites have sprung up in recent years in Jordan. Many of them include commentaries critical of the government, and some have published documents detailing the activities and spending of the royal family.