GENEVA: The United Nations did not deliver any aid to desperate Syrian civilians during the first full day of a fragile cease-fire because of security concerns, officials said Tuesday.

U.N. Syria envoy Staffan de Mistura told reporters in Geneva that he had "no information about any U.N. trucks moving at this stage," demanding "assurances that the drivers and the convoy will be untouched."

Spokesman for the U.N.'s humanitarian office (OCHA), Jens Laerke, separately confirmed that no U.N. convoys have deployed across a border or within Syria since the cease-fire call more than 24 hours ago.