A group of families who lost loved ones in the 9/11 terror attacks released a letter to President Obama Monday, just before he left on a trip to Saudi Arabia, saying there was “no excuse for refusing to reveal the truth, whatever it may be, about the events of 9/11 and to ensure that anyone responsible for the worst terrorist assault in history is held to account.”

The letter comes several days after reports that Obama will soon decide whether to declassify 28 pages of sealed documents suspected of showing a Saudi connection to the deadly terror attacks.

Obama was scheduled to leave Washington Tuesday and arrive Wednesday in the Saudi capital of Riyadh, where he will hold talks with King Salman.

Saudi Arabia has reportedly told the Obama administration and congressional leaders that it will sell billions of dollars in U.S. financial assets if Congress passes a bill to make the Saudi government legally responsible for any role in the 9/11 attacks.

The administration has tried to stop Congress from passing the legislation, a bipartisan Senate bill, since Saudi Foreign Minister Adel al-Jubeir last month told Washington lawmakers his country’s position, according to The New York Times.

In their letter to Obama, the 9/11 families said, “We were pleased to hear news reports, uncertain and conflicting as we may find them, that you are now reconsidering declassification of sections of the 9/11 Joint Inquiry report that address possible involvement in the attack by persons and institutions for which the Saudi government has responsibility.

“That disclosure, of course, must extend beyond the so-called '28 pages' redacted in the public version of the report and encompass all information bearing on the subject of possible Saudi involvement.“

Former Florida Democratic Sen. Bob Graham told Fox News last week that the White House told him a decision on whether to declassify the documents would be made within 60 days. 

Graham helped lead a 2002 congressional inquiry into the attacks.

The Bush and Obama administrations have refused to unseal the documents, arguing their release would jeopardize national security.