The fighter jets of the US-led military coalition were trying to hinder Russian airstrikes by flying inside the bombing zone in the Syrian town of Abu Kamal, Moscow said on Tuesday. The town is one of the last "Islamic State" (IS) strongholds in Syria, located on the Euphrates River near Iraq.

In order to ensure "safe passage for the retreating IS forces" the coalition jets "were trying to interfere with Russian fighter jets which were active in the region" said the Russian Ministry of Defense.

"With this goal, coalition fighter jets were entering the 15-kilometer (9 mile) airspace around Abu Kamal in order to impede the activities of the Russian air force," they added.

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Americans refused to bomb IS

Convoys of IS fighters were fleeing the town towards the Iraqi border, according to the footage recorded by Russian military drones last week. The Russian military "has twice approached the central command of the US-led coalition and suggested joint strikes to destroy the retreating IS forces on the east shore of Euphrates."

"However, the Americans categorically refused to conduct airstrikes against the IS terrorists, saying that, according to their data, the fighters were 'surrendering' and were protected by the Geneva convention on treatment of war prisoners," the Russian officials said.

The retreating IS fighters were equipped with "military vehicles and heavy weapons," they added. Russian military also reportedly asked the Americans why the jihadists were "regrouping in the zone controlled by the international coalition to conduct new attacks against the Syrian army in Abu Kamal," but received no response.

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IS to advance American interests

Moscow also accused the US of a plot to create a "pro-American" region on the Euphrates which would continue to oppose the Syrian government. According to the Defense Ministry, the routed Islamic Fighters would be sent back to reclaim the region themselves, but this time they would be flying the colors of the moderate Syrian Democratic Forces. The plans were dispelled by the rapid advance of the Syrian army, Moscow said.

"These facts are conclusive evidence that the United States, while imitating an noncompromising fight against international terrorism for the global community, in fact  provides cover for the IS units" in order to use them for advancing "American interests in the Middle East."

dj/jm (Reuters, Interfax)