Updated

A top Russian diplomat visiting Damascus says Syria has turned over material aimed at showing that a chemical weapons attack last month was carried out by rebels.

The Aug. 21 attack precipitated the current high tensions over Syria's chemical weapons and sparked a plan under which Syria is to abandon the weapons. A report by U.N. investigators confirmed chemical weapons were used but did not say by which side in the civil war.

The ITAR-Tass news agency quoted Deputy Foreign Minister Sergei Ryabkov as saying Wednesday that Syria told Russian officials the material "bears witness to the rebels participating in the chemical attack" but that Russia is not yet drawing any conclusions.

Ryabkov met Tuesday with Syrian foreign minister Walid al-Moallem and is expected meet President Bashar Assad on Wednesday.