Known as the "28 pages," the secret document was part of a 2002 congressional investigation of the Sept. 11 attacks and has been classified since the report's completion. It turns out there are actually 29 pages, sources said.
Sources said there are still some procedural steps that need to be taken before the release, which members of both parties in Congress and family members of victims have been seeking for years.
"This is great news," said Jerry Goldman, a lawyer who represents families of victims in a class-action suit, seeking to sue Saudi Arabia. "The families are happy just as the American people should be happy that information that has been kept hidden for well over a decade is finally coming to light."
Former Senator Bob Graham, who chaired the committee that carried out the investigation and has been pushing the White House to release the pages, said Thursday he was "very pleased" by the news.
"It is going to increase the questioning of the Saudis' role supporting the hijackers," Graham told CNN. "I think of this almost as the 28 pages are sort of the cork in the wine bottle. And once it's out, hopefully the rest of the wine itself will start to pour out."
Graham added, "Would the U.S. government have kept information that was just speculation away from American people for 14 years if somebody didn't think it was going to make a difference?"
Rep. Adam Schiff, a member of the House Intelligence Committee, said the report will be posted on line soon.
"The House Intelligence Committee will get the redacted report today or tomorrow," the California Democrat said. "The Senate and House intel committees should then give the formal go ahead to release the report since they originally produced it."
Under pressure from the victims' families and lawmakers, President Barack Obama said in April his administration would declassify the pages.
Sources told CNN that intelligence agencies, law enforcement and the State Department have all reviewed and approved the release of the pages with "minimal redactions."
One of those who wants to read the pages is Terry Strada, who has been pushing for the right to sue Saudi Arabia over its alleged involvement in the attack. Her husband, Tom, was working on the 104th floor of the North Tower when the planes struck. The couple's third child had been born just four days eariler.
"All of this could be settled if we would just release the 28 pages and let everyone see what's in there," Strada said.
"If it was just this low-level ... government officials in the Saudi Arabian government, then they have nothing to worry about," she added. "The American people deserve this just as much as the 9/11 families deserve it, but we're the ones that are suffering by not having them released."
For its part, the Saudi government is also calling for the pages to be made public so that it can respond to any allegations, which it has long called unfounded.
"We've been saying since 2003 that the pages should be released," said Nail Al-Jubeir, director of communications for the Saudi embassy. "They will show everyone that there is no there there."