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WASHINGTON, July 22 (Reuters) - The United States will on Tuesday release intelligence backing its assertion that the Malaysian airliner that crashed in Ukraine was brought down by a missile fired from the separatist-controlled area, the State Department said.

Spokeswoman Marie Harf told reporters the intelligence community would later in the day "be further declassifying information and will be putting out additional information that supports what we have said."

Harf repeated the U.S. belief that the plane, with nearly 300 people on board, was shot down by a Russian-made SA-11 ground-to-air missile fired from an area controlled by separatists close to the Russian border in eastern Ukraine. (Reporting by Lesley Wroughton and David Storey; Editing by Jim Loney)

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