Russia has been the subject of intense international criticism for its support of Syrian President Bashar al-Assad's regime and for blocking any international efforts to take stronger action.
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Some Syria observers see the shipment as undermining Russia's insistence that it opposes intervention in the conflict. The Telegraph's Middle East correspondent, Richard Spencer, writes:
"Russian arguments against direct involvement could now be strongly questioned by the British and Americans: 'Who is intervening in the crisis here? Who is pouring fuel on the flames? If you are providing attack helicopters to the Syrians how can you possibly say you are not intervening in the crisis?'"
Mr. Spencer speculated that this is likely to be followed with a stepping up of Western support for the rebels, perhaps through arms supplies.
Russia was also preparing to send military personnel and ships to its Tartous base, purportedly to secure it and to evacuate Russian nationals in case the conflict made it necessary, according to some reports. The US is reluctant to criticize the move because it often takes similar steps during international crises to protect its own defenses, reports The Wall Street Journal.