The opposition suspects that President Assad is trying to cover his tracks before allowing any international groups in to minister to the stricken city of Homs. Widespread reports of gruesome massacres and summary executions make that charge sound likely.
The Red Cross has been refused permission to deliver aid to the Baba Amr district of the bombed-out Syrian city of Homs, despite earlier getting the go-ahead from the authorities.
ICRC President Jakob Kellenberger said the hold-up was "unacceptable".
The delay has given rise to opposition allegations that government forces were trying to get rid of evidence of summary killings.
Baba Amr has suffered heavy bombardment by government forces in recent weeks.
The rebel Free Syrian Army (FSA) said on Thursday it was leaving the district in a "tactical withdrawal".
On Friday the UN human rights office said it had received reports of a "particularly grisly set of summary executions" of 17 people in Homs.
Two French journalists injured last month in the shelling and smuggled out of Homs into Lebanon are being flown back to Paris.
Edith Bouvier and William Daniels will be met by President Nicolas Sarkozy when they arrive.
Mr Kellenberger said in a statement that the seven-lorry aid convoy carrying food, medicine and blankets, along with ambulances from the Syrian Red Crescent, would stay in Homs overnight in the hope of entering Baba Amr "in the very near future".
Earlier, Syrian authorities had green lighted the convoy to enter the besieged neighborhood of Baba Amr where Syrian rebels had held out for several days despite Assad sending in tanks and firing his artillery indiscriminately, killing hundreds of civilians.
But it is probable that the hold up is due to having to clean up the streets of bodies who bear evidence of being summarily executed. Already, some Syrian commanders are probably looking ahead to war crimes trials once Assad is history.
The Red Cross will try again tomorrow.