By BRADLEY KLAPPER, Associated Press
WASHINGTON (AP) — The U.S. is trying to leverage new evidence that Syrian President Bashar Assad's government used chemical weapons, and make a fresh diplomatic and possible military push with allies to end the country's civil war.
This renewed effort starts with Secretary of State John Kerry's trip to Moscow this coming week for talks with leaders in Russia, the Syrian government's most powerful international friend.
Russia, alongside China, has blocked U.S.-led efforts three times at the United Nations to pressure Assad into stepping down.
Officials say the U.S. hopes to change Moscow's thinking with two new arguments: the evidence of chemical weapons attacks and American threats to arm the Syrian rebels.
Russia represents the most difficult diplomatic test as the U.S. tries to assemble a coalition to halt the war.
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