However, the Russian Ministry of Defense said Monday that it had begun working with Arab and Kurdish groups operating east of the Euphrates River, an area of operations for the USA advisers and the US-backed Syrian Democratic Forces, highlighting an increasingly complex battle space. And the new figures likely mean a more accurate count of troops who have already been in Syria for some time.
In Syria, under Obama administration accounting practices known as Force Management Levels, the Pentagon only acknowledged 503 troops in Syria, though officials privately admitted there were significantly more forces there.
The Pentagon's new public numbers reflect an approximation of deployed troops as of Wednesday, Manning said.
"To ensure an enduring defeat of ISIL, the coalition must ensure it can not regenerate, reclaim lost ground, or plot external attacks", he said.
"While the nature of USA support to partner forces will adjust as the coalition shifts from from major urban combat operations to stabilization tasks, U.S. support will not end until the enduring defeat of ISIS and will be determined by conditions on the ground", Pentagon spokesman Eric Pahon said in a written statement Tuesday outlining the United States strategy in Syria going forward. The 1,500 or so previously undisclosed troops in Syria include traditional combat forces like infantry, artillery and forward air controllers trained to call in airstrikes, as well as support personnel, said Eric Pahon, a Pentagon spokesman.
Prominent British militants such as Mohammed Emwazi, known as Jihadi John, and Sally Jones, have been reportedly killed by British or US forces since travelling to fight for Islamic State.
The U.S. troops are also focused on training local police forces, ensuring humanitarian aid can flow into areas where it is needed and ensuring local governance where U.S. -backed forces liberated land from ISIS, he said.