Valerie Amos, the humanitarian chief for the United Nations, accompanied members of the Syrian Red Crescent to the Baba Amr district of Homs, the BBC reports.
Video footage given to London's Channel 4 News this week depicts victims of alleged torture at a military hospital in Homs.
The Syrian military took control over the Baba Amr district in raids last week. It was a center of activity tied to anti-government forces.
The International Committee of the Red Cross and Syrian Red Crescent have struggled to gain access to the area. Syrian Foreign Minister Walid al-Moallem told Amos he was committed to working with the United Nations so long as Syria's independence was respected.
He said "the Syrian leadership is doing its best" to provide assistance to all citizens despite the burdens of "unfair sanctions" imposed by Western and Arab countries, the official Syrian Arab News Agency reports.
The United Nations estimates that at least 7,000 people have died in Syria during an uprising that began a year ago. U.N. officials have recommended referring Damascus to the International Criminal Court, though the Syrian government maintains its dealing with domestic terrorists.