Updated

Three U.S. diplomats stepped up pressure against the Syrian government on Friday by accusing it of continuing to use chemical arms against its opponents in the country's four-year civil war.

The American ambassador to The Hague-based Organization for the Prohibition of Chemical Weapons, Robert Mikulak, cited a "steady stream" of accounts that the government is using chlorine as a chemical weapon, as recently as this month.

Deputy Secretary of State Antony Blinken told reporters that accounts by people in Syria over such chemical attacks are "strong and credible."

And Samantha Power, the U.S. ambassador to the United Nations, said evidence makes clear that Syria is killing people by dropping chlorine-filled barrels from helicopters onto neighborhoods and stressed that the international community needs to assign blame to Damascus.

"As you know, only the regime has helicopters," Ms. Power said. "So we believe the factual record is quite straightforward and devastating in terms of Syrian regime use."
Syria, which denies it uses chemical weapons, agreed in 2013 to a U.S.-Russia-sponsored plan to dismantle its chemical-arms network and join an international treaty banning their use to avert the threat of a U.S. attack.

In the past, President Bashar al-Assad's allies in Beijing and Moscow have vetoed resolutions condemning his regime.

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