The World Day Against Cyber Censorship, on March 12th, is a protest against state filtering of the web. It comes as the Australian Government is finalising its live trials for a much-debated internet filter.

Amnesty International and Reporters Without Borders (RSF) wrote an open letter to the US tech giants asking them to join the protest.

"World Day Against Cyber Censorship is a day to advance and celebrate a free internet as an open window to the world and denounce the attacks made on the free flow of information online," the organisations said. "In the spirit of fostering freedom of expression, we are asking that you do not censor any of your search engines or blog platforms anywhere around the world on this day," they said.

"We urge you, on March 12th, to champion the vision of the internet as a free space for everyone, regardless of nationality or geographic location, and fulfil the idea of a truly worldwide web - even if just for one day.

RSF and Amnesty said that currently, there are more than two dozen countries regularly restricting internet access.

RSF staged the first "World Day Against Cyber Censorship" last year and plans to mark the day with a report on the state of internet freedom worldwide. -- AFP