Manning undid part of secret U.S. intelligence sharing - testimony

U.S. Army Private First Class Bradley Manning is escorted into court for the second day of the sentencing phase in his military trial at Fort Meade, Maryland August 1, 2013. REUTERS/James Lawler Duggan

FORT MEADE, Maryland (Reuters) - Washington had to restrict access to an intelligence-sharing system after the biggest leak of classified information in U.S. history, a former official said on Friday at the sentencing hearing of Bradley Manning, the soldier convicted of the leaks.

Tightening access to the system undid the very benefits the system was meant to provide, according to Susan Swart, a former U.S. State Department official who was responsible for the movement of diplomatic cables when they were leaked and published by the anti-secrecy website WikiLeaks in 2010.