The World Press Freedom Index ranks 180 countries on indicators such as media independence, self-censorship, the rule of law, transparency and abuses.

This year's report warned of a climate of fear that has seen world leaders "developing a form of paranoia about legitimate journalism."

Christophe Deloire, secretary general of the Paris-based group told AFP there had been a decline in all parts of the world, with Latin America of particular concern.

"All of the indicators show a deterioration. Numerous authorities are trying to regain control of their countries, fearing overly open public debate," he said.

"Today, it is increasingly easy for powers to appeal directly to the public through new technologies, and so there is a greater degree of violence against those who represent independent information," he added.