On Saturday, SANA announced it had released 30 detainees whose "hands were not stained with the blood of the Syrians." The state-run agency also said hundreds of detainees had been released in November, December and January.
But Ban said this week there has also been no significant release of detainees and no substantive progress on providing humanitarian assistance, despite the Syrian regime's acceptance of the peace plan in March. He also said Syria has not lived up to its promise to withdraw troops from cities.
The Annan plan also calls for the right to demonstrate peacefully. Opposition groups said security forces in Aleppo and Daraa fired at demonstrators on Friday, the day of the week nationwide protests are held, activists said. At least 57 people were killed across Syria on Friday.
Syria has been engulfed in violence for 13 months, since the government started a fierce crackdown on peaceful protests against President Bashar al-Assad's regime. The president's family has ruled Syria for 42 years.
The United Nations estimates that at least 9,000 people have died since the protests began, while activist groups put the death toll at more than 11,000.