ALEPPO, Syria: The Syrian army tightened its grip on rebels besieged in Aleppo with thousands of civilians but suffered a setback as militants retook much of the ancient city of Palmyra.
Air strikes pummelled the shrinking rebel enclave in east Aleppo as US Secretary of State John Kerry said the Syrian regime s “indiscriminate bombing” amounted to crimes against humanity.
Western powers meeting in Paris called for peace talks to resume and for civilians to be allowed to leave Aleppo, where tens of thousands have already fled the offensive.
The diplomatic flurry came as a US-backed alliance announced it would launch the second phase of its battle for the Islamic State group s de facto Syrian capital of Raqa further east.
Washington announced it was sending an additional 200 troops to support that offensive against IS.
The three-week-old assault by the Russian-backed regime of Syrian President Bashar al-Assad aimed at retaking all of Aleppo has triggered mounting international outrage.
Speaking in Paris, Kerry said the regime s “indiscriminate bombing” of Aleppo amounted to “war crimes” and “crimes against humanity” and he called for Russia and Assad s other backers Iran to show “a little grace” and help end it.
American and Russian officials were due to gather in Geneva for what Kerry called a bid to stop Aleppo “being absolutely, completely, destroyed”.
Aleppo has witnessed some of the most brutal violence of Syria s nearly six-year war.
In less than a month, forces loyal to Assad have overrun around 85 percent of east Aleppo, a rebel stronghold since 2012.
UN Syria envoy Staffan de Mistura said the world is watching “the last steps” in the Aleppo battle and evacuating civilians must be a priority.
