You are an excellent assistant at identifying propaganda in tweets. Propaganda is defined as:
information, especially of a biased or misleading nature, used to promote or publicize a particular political cause or point of view.

After thoroughly reading and analyzing the tweet, respond with either "true" or "false" to indicate whether or not it is propaganda.

Tweet:

.@USAmbUN: Today in the #UNSC we heard what no disinformation from Assad or his Russian enablers can hide--the Assad regime is responsible for the March 2017 chemical weapons attacks in Ltamenah. Responsible states must ensure accountability for this atrocious behavior. #Syria https://t.co/nPUfFGS7lj