The US congresswoman who has argued for Assad to be kept in power has now taken a trip to Syria, in what her office is calling a "fact-finding" mission.
Residents of government-held areas of the Syrian city of Deir az-Zour have expressed fears of mass killings as the Islamic State group continues its advance on the city.
Key rebel group Ahrar al-Sham said on Wednesday it will not take part in peace talks in the Kazakh capital next week aimed at ending Syria's nearly six-year-old war.
Antonio Guterres, the new UN chief, says the Syrian conflict has triggered instability in the Middle East and terrorist attacks across the world.
Nine Russian and eight Turkish planes took part in the 'first joint air operation' in the area around the Syrian town of al-Bab.
Blog: A few of The Donald's thoughts on the six-year civil war and world's most significant humanitarian disaster...
Comment: In his recent Times interview, Trump displayed a callous attitude to Syria, and reiterated his deeply flawed plan of a grand US-Russia coalition against IS, writes James Snell.
Staff General Talib al-Sheghati says the left bank of the Tigris River that divides the city has been 'liberated' and that 'normal life' will return to the saved areas soon.
Comment: Guterres will be in a better position to give fresh impetus to the UN political process aimed at finding a political solution to the Sahara conflict, writes Samir Bennis
Iranian officials say they are 'hostile' to the presence of the United States joining Syrian peace talks in Kazakhstan next week and that they have not invited them.