(CNN) The US military accused Russia on Thursday of blocking the delivery of critical aid to the Rukban refugee camp in Syria, a desert camp that the United Nations has described for months as in a "desperate" situation.

"Russia has again refused to support a UN delivery of humanitarian assistance from Damascus to the Rukban internally displaced persons camp despite US security guarantees," US Navy Capt. Bill Urban, a spokesman for US Central Command, told CNN in a statement.

"Counter to the false claims made to the United Nations by Russia, conditions are ripe for this critical aid to be delivered to the people of Rukban, where conditions remain dire," he added.

The camp sits within the 20-square-mile de-confliction zone that surrounds the US base in Al Tanf, Syria, which was established by the Russians and the US-led coalition to prevent the two sides from coming into accidental contact.

On Wednesday, Russia's Ministry of Defense accused the US of intentionally blocking aid from reaching the inhabitants of Rukban in a bid to attract recruits to the Maghawir Al-Thawra, or MaT, a local group of fighters the US trains to fight ISIS.

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