BAGHDAD, Jan 6 (Reuters) - The United States-led military coalition against Islamic State said on Monday that it was pulling out of Iraq and would be repositioning forces over the next few days and weeks, a letter seen by Reuters showed.

"Sir, in deference to the sovereignty of the Republic of Iraq, and as requested by the Iraqi Parliament and the Prime Minister, CJTF-OIR will be repositioning forces over the course of the coming days and weeks to prepare for onward movement," read a letter from United States Marine Corps Brigadier General William H. Seely III, the commanding general of Task Force Iraq.

The authenticity of the letter, which was addressed to the Iraqi defence ministry's Combined Joint Operations Baghdad, was confirmed to Reuters independently by an Iraqi military source.

"We respect your sovereign decision to order our departure," it said. (Reporting by Ahmed Aboulenein Editing by Chizu Nomiyama)

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