Syrian state television says a bomb has exploded near a hotel used by United Nations observers in Damascus, wounding three people.

The report said the blast Wednesday was caused by a bomb planted on a fuel truck.

U.N. officials did not immediately comment, but none of the wounded are believed to be U.N. staff.

The U.N. Security Council is due to discuss the situation in Syria on Thursday, days before the observer mission's mandate expires on August 19.

China's official People's Daily newspaper on Wednesday criticized Western nations for talking about the prospect of a no-fly zone of Syria, saying such comments undermine U.N. mediation efforts and harm the unity of the Security Council.

The paper also reiterated China's commitment to a diplomatic solution to the crisis. China has joined Russia in vetoing U.N. Security Council resolutions threatening Syria with sanctions for using heavy weapons against civilians.

U.S. Secretary of State Leon Panetta said earlier this week he is confident the United States could enforce a no-fly zone, but that it is not a top priority. He also says Iran is trying to develop and train a militia in Syria to fight rebels on behalf of Syrian President Bashar al-Assad's government.

His comments come as foreign ministers of the 57-member Organization of Islamic Cooperation are holding a summit in Mecca after agreeing to recommend suspending Syria from the group. The foreign minister of Iran – one of Syria's strongest allies – said his country will never accept the proposal.