Jaafari said Damascus has extended visas to hundreds of people working for the Office for the Coordination of Humanitarian Affairs (OCHA), which is led by Amos. "Any minimal cases here and there" of problems "wouldn't affect the overall picture of our cooperation with OCHA," he said.
In Syria, opposition activists blamed the war for more than 100 deaths Friday in a series of incidents.
A car bomb erupted in front of a mosque in the Damascus suburb of Wadi Barada, killing at least 44 people and wounding more than 200, the Local Coordination Committees of Syria said.
Other attacks resulted in 33 deaths in Daraa; 11 in Hama; 11 in Deir Ezzor; five in Latakia; three in Homs; three in Aleppo; and three in Idlib, the LCC said.
Syrian state television reported that the military ambushed and killed more than 50 "terrorists" in al-Otaiba, a town in the suburbs of Damascus. The London-based Syrian Observatory for Human Rights put the number of rebel dead at 20.
Amid accusations by government and opposition forces that each side has used chemical weapons, the Syrian government continued this week to comply with its agreement to rid the country of its stores of such arms, the Organization for the Prohibition of Chemical Weapons said.
On Thursday, the OPCW said its inspectors had visited the 19th of 23 chemical weapons sites disclosed by Damascus.
President Bashar al-Assad on Thursday thanked workers at the ministries of electricity and petroleum for restoring services a day after much of the country was plunged into darkness by what the state-run Syrian Arab News Agency said was sabotage of a gas pipeline.
According to the United Nations, more than 100,000 people have died in the conflict, which began in March 2011 when government forces cracked down on peaceful protesters.