UN Security Council
UN Security CouncilReuters

The United Nations (UN) Security Council on Sunday condemned the "heinous and cowardly murder" of British aid worker David Haines by the “Islamic State” (IS).

"This crime is a tragic reminder of the increasing dangers humanitarian personnel face every day in Syria," the council emphasized in a statement, adopted unanimously by its 15 members and quoted by AFP.

The statement called for aid workers to be respected in conflict zones and "stressed again that IS must be defeated and that the intolerance, violence and hatred it espouses must be stamped out."

The council members emphasized that "such continued acts of barbarism perpetrated by IS do not intimidate them but rather stiffen their resolve that there has to be a common effort" against it and other jihadist groups.

The council also called for the "immediate, safe and unconditional release of all those who are kept hostage" by IS and other groups associated with Al-Qaeda.

It urged all states "to cooperate actively" with Britain's efforts to bring the perpetrators of Haines' execution to justice.

IS on Saturday released a video showing the execution of Haines in the same grisly manner as the murder of two American journalists in recent weeks.

The video, titled “A Message to Allies of America,” appears to show Haines clad in an orange jump-suit kneeling beside a man who speaks in the same London-accented English as the apparent executioner in two previous videos.

IS had released two previous videos showing the execution of the American journalists James Foley and Steven Sotloff. The group threatened to kill Haines at the end of the Sotloff video.