Teams from the International Committee of the Red Cross and the Syrian Arab Red Crescent did not enter the battered Baba Amr district of Homs, ICRC Damascus spokesman Saleh Dabbakeh, told the AFP news agency.
"No teams entered on Friday Baba Amr, and [authorities] have not allowed entry of aid," he said.
"We are still in talks," he said, shortly after a Damascus-based ICRC official told AFP that a team went into the neighbourhood on Friday to assess the needs while negotiations were continuing with authorities to allow aid in.
Government forces overran Baba Amr on Thursday after nearly a month of bombarding the opposition-held neighbourhood of Syria's third-largest city.
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