A UN committee on Tuesday voted to create an international day to protect journalists as media activists condemned the mounting number of reporters killed on duty.

The Reporters Without Borders group welcomed the move and said 89 journalists were killed while working in 2012, the highest number in nearly two decades.

The UN General Assembly's human rights committee voted unanimously to make November 2 each year the International Day To End Impunity For Crimes Against Journalists.

November 2 is the day that French radio journalists Ghislaine Dupont and Claude Verlon were killed by militants in Mali this year.

More than 70 countries co-sponsored a resolution which called on UN states "to do their utmost to prevent violence against journalists" and to carry out "impartial, speedy and effective investigations" of attacks on media workers.

Highlighting the number of journalist killings, Reporters Without Borders secretary general Christophe Deloire said "another 52 journalists have been killed in connection with their work since the start of 2013."

Deloire said the journalists' activist group was "outraged" by the killings of the French reporters in Mali "as we have been by the murders of fellow journalists in Syria, Somalia, Pakistan, Brazil and other parts of the world in 2013."

"The safety of journalists is an essential prerequisite for achieving freedom of expression, democracy, social development and peace," Deloire added.