Russia, Syria's most important ally, has argued that aid should be delivered from within the country across conflict lines and just one crossing point is needed.

In a joint statement issued Sunday afternoon, the ministers said the decision will "prevent millions of Syrians from receiving aid they urgently require."

The UN wants an aid convoy, with more than 100 trucks accompanied by some 250 UN and Syrian Arab Red Crescent personnel, to leave for the isolated Rukban camp on the Syria-Jordan border by Feb. 5.