Hillary Clinton said Tuesday that Russia has attack helicopters on the way to Syria to aid dictator Bashar al-Assad's regime, the Associated Press reported.
"We have confronted the Russians about stopping their continued arms shipments to Syria," Clinton told reporters, according to Reuters. "They have, from time to time, said that we shouldn't worry - everything they are shipping is unrelated to their (the Syrian government's) actions internally. That's patently untrue."
The US Secretary of State added that Russia's actions "will escalate the conflict quite dramatically," Reuters reported.
"We know that the Assad regime is using helicopter gun ships against their own people," Pentagon spokesman Captain John Kirby said, according to Reuters.
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Clinton made her comments at a public appearance with Israeli President Shimon Peres, according to the AP.
Victoria Nuland, the State Department spokeswoman, did not elaborate on where Clinton was receiving her information from, but noted that she was referring to new helicopters and not existing choppers in Syria's fleet, according to Agence France Presse.
"She's concerned about helicopters on the way," Nuland told AFP. "That's a different matter than whether there are already Soviet-made helicopters or Russian-made helicopters that are being used by the regime," which is a close ally of Moscow's.
The news of Russia's support comes as United Nations-Arab League envoy Kofi Annan is working to build a coalition of countries (which includes Russia) to develop a “road map for political transition” in Syria, Bloomberg Businessweek reported.
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Around 13,000 people have died in Syria's 15-month conflict, opposition groups told the AP, which threatens to escalate into civil war. The US and its allies have hinged their hopes on increasing Syria's isolation with sanctions against Assad's government that would curb the dictator's military campaigns, according to the AP.
"We are watching the situation very closely," Clinton said.