- US and Russia divided over ceasefire agreement in Syria
- Other actors such as Turkey and Iran relatively quiet on the subject
- Iran and Turkey met on the sidelines of the UN -- their involvement is crucial
(CNN)The accusations fly between Washington and Moscow. Accounts multiply of just what happened to the Aleppo aid convoy struck on Monday night: claim is met by denial, evidence by obfuscation. Even by the standards of Syria's merciless conflict, a new low has been reached.