United Nations chemical weapons inspectors are back in Syria to investigate the use of the banned materials in the country's two-and-a-half-year civil war.
The team led by Ake Sellstrom flew into neighboring Lebanon Wednesday and then traveled by car to Damascus.
It first went to Syria last month to investigate three attacks, including one in March outside of Aleppo that the Syrian government and rebel fighters blame on each other.
The team shifted its focus on the two-week mission to a recent attack outside Damascus, where it concluded that chemical weapons were used. The team's mandate does not include assigning blame for any chemical attacks.
Also Wednesday, a group of 13 rebel groups issued a joint statement rejecting the main opposition Syrian National Coalition, saying it no longer represented their interests. The group, which includes the al-Qaida-linked Nusra Front, called on those fighting against President Bashar al-Assad to unite under an Islamic framework.
Syrian President Bashar al-Assad's U.N. Ambassador Bashar Ja'afari told VOA's Persian service that the opposition is divided because it is working on behalf of multiple foreign intelligence services.
"It depends on which capital is behind (a particular) wing of the opposition. You have an opposition working for the Saudi agenda, another opposition working for the Qatari agenda, then you have an opposition working for the American agenda, the British, the French. Each one of these wings is implementing the policies of these foreign agendas. This is the main reason these opposition (groups) cannot be unified."
Syrian opposition groups acknowledge receiving foreign assistance but say their agenda is to end the Assad family's four-decade rule of Syria.
Meanwhile, in New York, diplomats are continuing to work on a draft resolution to enforce an agreement for Syria to give up its chemical weapons.
U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov met Tuesday on the sidelines of the U.N. General Assembly, but failed to agree on the key points of the document.
U.S. officials say points of contention remain as the two sides seek a deal on the language of the resolution. The U.S. and Russian ambassadors to the U.N. are tasked with working out the final language.
Russia opposes a resolution that mentions Chapter VII of the U.N. charter, which includes military and non-military action to enforce decisions.
Russia has long opposed the idea of military intervention, and has vetoed three attempts to sanction Syria at the U.N. Security Council.
Russian Deputy Foreign Minister Sergei Ryabkov said Tuesday the resolution could mention the Chapter VII article that permits force or sanctions, only if the U.S.-Russia chemical weapons accord is violated by either side in the Syrian conflict.
Speaking at the General Assembly Tuesday, U.S. President Barack Obama criticized doubters who questioned whether Syria's president carried out a chemical attack last month near Damascus. U.S. intelligence says the attack killed 1,400 people.
Syria's civil war has forced two million people to flee the country, with another 4.5 million displaced within Syria. In total, the conflict has forced more than a quarter of Syria's population to leave their homes.
Most of those who have fled the country have gone to neighboring countries, including Jordan, Lebanon, Turkey and Iraq.