Daniel MacSweeney, the Yemeni delegate at the International Committee of the Red Cross, said aid workers had met with more than 5,800 Yemeni prisoners in prisons across the country this year.
He said ICRC representatives were monitoring prison conditions for Yemeni detainees and working to ensure they had access to suitable healthcare.
"The ICRC has entered into discussions with President Abdo Rabbu Mansour Hadi with the aim of reaching a written agreement that would give the ICRC more systematic access to detainees held by the Yemeni state authorities," he said in a statement Wednesday. "We have received an encouraging response and are making progress on this issue."
MacSweeney said aid workers were trying to enhance the protection for civilians in Yemen by pressing for the need to distinguish between civilians and combatants in armed conflict.
National security in Yemen is challenged by the heavy presence of al-Qaida. Separatist ambitions in southern provinces are complicating a fragile situation in Yemen.
Hadi met last week with U.S. Secretary of State John Kerry and other high-ranking officials. He said his country was working to chart a new course two years after the so-called Arab Spring political upheaval in the Middle East and North Africa.