WASHINGTON — The US government on Thursday announced the release of the famed "Pentagon Papers," 40 years after the once top-secret Vietnam War documents were leaked to the media.

The National Archives, the massive US repository for historic books and documents, announced that the files, now declassified, will be accessible starting next month at the Richard Nixon presidential Library in Yorba Linda, California.

Officially titled "United States-Vietnam Relations, 1945-1967: A Study Prepared by the Department of Defense," the top-secret report detailed US political and military involvement in Vietnam from 1945 to 1967.