Regime forces amass around Aleppo as diplomacy falters

09-30-2016 • cnn.com, By Barbara Starr and Elise Labott

As an estimated 10,000 Syrian-led ground troops amass east of Aleppo, the US is considering a tougher response to Russia over its support for the Assad regime and its role in the bombardment of the city, senior administration officials told CNN.