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When the president leaves for a trip to Saudi Arabia on Tuesday an unresolved issue will go with him: did the Saudis play some role in supporting the hijackers responsible for the attacks on September 11th?

The question is being raised in the wake of a renewed push to declassify 28 pages of a 838-page congressional report on the worst terror attack on American soil.

The so-called “28 pages” are locked away in a secure basement room at the Capitol and although they can be read by members of Congress, the pages remain classified.

Related: Classified documents Contradict FBI on Post-9/11 Probe of Saudis, Ex-Senator Says

That the two of the hijackers involved in the September 11th attacks landed in Los Angeles, moved to San Diego and obtained housing, language lessons and identification is widely known.

However, those 28 pages could shed more light on the money and connections used to do so and are said to include information “suggesting specific sources of foreign support for some of the September 11 hijackers while they were in the United States,” according to the chapter’s introduction in the report.

Former Senator Bob Graham told “60 Minutes” in an interview, “I think it is implausible to believe that 19 people, most of whom didn't speak English, most of whom had never been in the United States before, many of whom didn't have a high school education — could've carried out such a complicated task without some support from within the United States.”

King Salman will meet with President Obama this week. - / AFP - Getty Images

Graham is the former chairman of the Senate Select Committee on Intelligence and co-chair of the bipartisan joint congressional inquiry into intelligence failures surrounding the attacks. He wants those pages declassified and told “60 Minutes” he believes support for the hijackers came from the government, wealthy people and charities in Saudi Arabia.

The “60 minutes” report reignited debate and interest in the documents, according to Brian McGlinchey, who runs the website 28pages.org, which describes itself as a hub for the movement to declassify those pages.

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“I definitely think there is some momentum,” he told NBC News by phone.

The timeline to get this done appears to finally be speeding up.

The White House says the Director of National Intelligence hopes to complete the review process by the end of the year. And Graham told the Tampa Bay Times it could happen in the next month or two based on a phone call he got from a senior Obama administration official.

But the White House would not confirm that timeline and also wouldn’t confirm the president even has read the 28 pages.

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It also seems highly unlikely those pages will be made public before the president’s trip to Saudi Arabia. The relationship between Saudi Arabia and the United States has been described by senior administration officials as both complex and complicated, made more precarious by the recent nuclear deal with Iran. This is Obama’s fourth trip to Saudi Arabia, more than any other president. The visit will kick off with a bilateral meeting between Obama and the Saudi King Salman.

White House Press Secretary Josh Earnest said he did not know if allegations of Saudi support for the hijackers might come up during the trip and pointed out the 9/11 Commission has already looked closely at that possibility and ruled it out.

Former al-Qaeda leader Osama bin Laden at an undisclosed place inside Afghanistan. AFP - Getty Images, file

“Saudi Arabia has long been considered the primary source of funding. But we have found no evidence that the Saudi government as an institution or senior Saudi officials individually funded the organization,” Earnest quoted from the 9/11 Commission report during a briefing last week.

Jim Kreindler and Sean Carter, lawyers representing the families of victims of September 11th attacks, are fighting to have those 28 pages declassified as part of a lawsuit against the government of Saudi Arabia.

Kreindler said the White House could be doing a lot more ensure transparency.

“The administration views the 9/11 families suit as an impediment to the U.S.-Saudi relationship,” he told NBC News.

He also points to the position the administration took in 2009, which advocated the Saudi kingdom should be immune from the claims filed by the families of victims because it has sovereign immunity.

“I think that he should raise not only the 28 pages, but the unresolved disputes between 9/11 families and Saudis generally,” Carter said of the president’s upcoming meeting with King Salman.

Related: Obama, Gulf Leaders Seek to Shore up Regional Security

But, not everyone agrees those 28 pages would make a difference.

Congressman Adam Schiff, the current ranking Democrat on the Select Committee on Intelligence also wants the 28 pages declassified, but for another reason. He thinks it will put an end all the speculation that the Saudi government was involved.

"The 9/11 Commission investigated these claims and was never able to find sufficient evidence to support them," Schiff said in a statement.

The White House points to a past record of openness and transparency, including declassifying part of Senate’s report on the CIA interrogation program and making public instances in which non-combatants were killed in counterterrorism operations oversea. The review of the Joint Congressional Inquiry regarding the 9/11 attacks “remains underway, but every effort is being taken to complete it before the end of the Administration”.

“Until these 28 pages are freed from the vault, the American people can’t make an informed evaluation of their government’s past and present foreign policy and its execution of the war on terror,” McGlinchey said.