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The U.S. and Russia are trying this week to bridge their differences on Syria to find a way to resolve the complicated war there. And this is happening as the military conflict has only intensified.
A U.N. Commission of Inquiry has documented this upsurge of violence in a new report out today. It blames Syrian and Russian air raids for most of the attacks on civilian areas but adds that all sides are responsible for a long list of atrocities. NPR's Michele Kelemen has the latest.
MICHELE KELEMEN, BYLINE: There was a glimmer of hope earlier this year when the U.S. and Russia managed to get the warring sides in Syria to abide by a truce. It fell apart quickly. And a U.N. investigator out with a new report today, Vitit Muntarbhorn, is worried.
VIVIT MUNTARBHORN: Despite the glimmer of hope in February, there has been an evident militarization since the end of March. And that is a great shame and injustice vis-a-vis the civilian population - innocent people.
KELEMEN: Muntarbhorn is a member of an International Commission of Inquiry which has been documenting possible war crimes in Syria. The report released today calls for an end to indiscriminate attacks on civilian areas, including hospitals and clinics.
MUNTARBHORN: That message is particularly relayed to those who control the air. And that pertains particularly to the pro-government forces, while not forgetting that not so far away, we also have shelling by anti-government armed groups and terrorist groups.
KELEMEN: As you hear there, the human rights investigator is careful not to put the blame only on the Syrian regime and its Russian backers, though they are the ones that have been carrying out deadly air raids on contested cities like Aleppo.
Another author pointed out that no one has been held to account for targeting hospitals and other civilian sites that are supposed to be protected by humanitarian law. A former U.S. envoy on Syria, Fred Hof, worries about that, too, saying there's little in place to rein in the Syrian president.
FRED HOF: For Bashar al-Assad in particular, creating mass civilian casualty events is an entirely cost-free affair.
KELEMEN: Hof, who's now with the Atlantic Council, says the U.S. wants Russia to use its influence with the Syrian president, Assad, to stop attacks on civilian areas and focus more attention on ISIS instead. But he says Secretary of State John Kerry has a weak hand.
HOF: And the fact is the Russians are playing a hand right now that is just filled with aces and kings because of their military intervention.
KELEMEN: Hof believes the Russian goal is to solidify Assad to make it harder for the U.S. and the Syrian opposition to push him aside. That may be one reason these U.S.-Russian talks on a cease fire are taking so long, adds another Syria watcher, Andrew Tabler of The Washington Institute for Near East Policy.
ANDREW TABLER: The question is is the cessation of hostilities agreement - is it really the road to a truce? Or is it a way for Assad to grind away at the opposition?
KELEMEN: On the sidelines of the G20 summit in China this week, President Obama met with his Russian counterpart, Vladimir Putin. And Syria was high on the agenda. But Obama cited gaps of trust.
And the two agreed only to have their top diplomats continue to work to revive a cease-fire. At the State Department today, spokesman Mark Toner said, quote, "we're not there yet."
MARK TONER: So it is extremely delicate, extremely sensitive. But we wouldn't still be in this conversation if we didn't think it was still worthwhile.
KELEMEN: He says the goal is to ease the suffering of the Syrian people. Toner was also asked today about new allegations that the Syrian regime is again dropping chlorine bombs on civilians. Toner says the U.S. is looking into that. Michele Kelemen, NPR News, Washington. Transcript provided by NPR, Copyright NPR.