Peter Maurer, president of the Geneva-based International Committee of the Red Cross, said his talks with Bashar Assad were "sober, to the point" and "clearly focused on humanitarian needs," such as releasing deliveries of food, medicine and other supplies to hundreds of thousands of people.
Maurer told reporters he also visited rural areas around Damascus where residents told him "horrific accounts of armed attacks" and left him shocked.
He said the accounts left him with no doubt that Syria is engulfed in civil war since "all features of armed conflict are unfolding in front of us."
Maurer, who just returned from a three-day visit, said the Red Cross assumes it has access to prison detainees based on Syria's obligations under international humanitarian law, but that Assad gave no firm promises of how that would be implemented.
Assad, he added, "expressed his readiness to address this issue."
Since the uprising began in March 2011, there have been tens of thousands of people detained in Syria, Maurer said, and "their basic rights must be upheld and they must be able to get in touch with their families."
Asked his impressions of Assad, Maurer, a veteran Swiss diplomat, declined to specify. But he said Assad and other ministers generally agreed on the need to reduce barriers to delivering aid.
At his first press conference at Red Cross headquarters since taking the helm of the Swiss-based organization, Maurer was asked what made him think Assad would honor commitments he makes.
"You have a saying in English: Proof of the pudding is in the eating," he replied.
At their meeting Assad asked "very detailed questions" that left Maurer convinced that "he is seriously interested in" trying to find solutions to the many challenges and problems, he said.
"The conflict is unfolding in a very different way in different parts of the country," Maurer said. "We are confronted with a new situation in a new context."
The Red Cross' assessment of the level of fighting, particularly that it is a civil war, has important legal and humanitarian ramifications because the group's role as overseer of the Geneva Conventions makes it is the arbiter of the rules of war.
That stature and its neutrality also lend it a unique role in the monitoring of prison conditions worldwide.
"The needs are growing while the violence is expanding," Maurer said. "Many men, women and children who could be saved are dying on a daily basis because they lack access to medical care."
Maurer said in answer to a reporter's question that the Red Cross was looking at ways of engaging similarly with the Syrian opposition, but that any such talks are made more difficult because of the fragmented nature of the armed anti-government groups.