Families of hundreds of 9/11 victims have told President Biden he is not welcome at this year’s memorial events marking the 20th anniversary of the attacks unless he declassifies government evidence beforehand that could link Saudi Arabia to the attack, according to a letter sent to the White House on Friday and obtained by The Washington Post.

“Six months ago the 9/11 community had great hopes that President Joe Biden would be the long lost champion of those directly affected by this murderous attack on our nation, finally placing the values of truth, justice, and accountability before the interests of the Kingdom of Saudi Arabia,” stated the letter, which was signed by about 1,800 family members of 9/11 victims, survivors and first responders.

They pointed to a promise Biden had made last October while campaigning for the presidency, in which he had vowed, if elected, to direct the U.S. attorney general to “personally examine the merits of all cases” where the government had invoked state secrets privilege and “to err on the side of disclosure in cases where, as here, the events in question occurred two decades or longer ago.”

“The 9/11 Families are right to seek full truth and accountability,” Biden wrote in a letter to a representative of the families then. “The loss endured by the 9/11 Families on that horrible day in 2001 is incalculable. Nothing I can say can compensate for their loss. I hope that your work in pursuit of justice and accountability can help bring them some small degree of closure.”

The 9/11 families on Friday said they are seeking investigative evidence uncovered by the bipartisan 9/11 Commission that implicates Saudi Arabian government officials in supporting the attacks. They added they have been frustrated by Justice Department and FBI officials who, through several presidential administrations, have “actively sought to keep this information secret.”

“As we approach the 20th anniversary of 9/11, and having been used as a political bargaining chip for two decades, our patience has expired,” their letter stated.

White House press secretary Jen Psaki on Friday told reporters that Biden administration officials have held several meetings with groups representing 9/11 families regarding their requests for government evidence and their policy priorities.

“That will continue to be a priority,” Psaki said.

Biden, meanwhile, had not forgotten about his campaign promise to ask the Justice Department to “work constructively” on the issue, Psaki added, without detailing how far along they were in that process.

“He remains committed to that pledge he made during the campaign,” Psaki said. “Of course, any steps would be taken by the Department of Justice.”

Brett Eagleson, an advocate for 9/11 families who lost his father in the attacks, said the White House’s response Friday was not sufficient and that they needed to see “tangible proof” the administration was truly committed to transparency before Sept. 11 this year. That would include beginning to see materials like an unredacted version of a 2016 FBI report from an investigation of Saudi government agents, along with phone records and other witness statements.

“These documents involve a terrorist attack that occurred 20 years ago, and there is no justification to withhold them,” Eagleson said in a statement. “Prior administrations have promised ‘reviews’ only to use them as delay tactics to protect the Saudi government and keep the American people in the dark. We hope the Biden administration finally provides the information our families have waited to receive for 20 years, so we can stand together with the President at Ground Zero on 9/11.”

Last year, as a presidential candidate, Biden visited both the 9/11 Memorial in Lower Manhattan and the Flight 93 National Memorial in Shanksville, Pa., for the 19th anniversary of the attacks. He reportedly is planning to attend the 9/11 memorial events in New York City next month.

Eagleson said the families’ ultimatum was not politically motivated, and that they had also implored Trump administration officials over the last four years to release the same government evidence.

In an interview Friday with The Washington Post, Eagleson said he met with President Donald Trump in the White House in 2019 — along with several other 9/11 families — and that Trump told them the release of the documents was “very, very imminent” and asked them not to publicly criticize him.

“President Trump led us to believe that he was going to declassify the documents. We were talking to the administration all along and they slow-played us and hoodwinked us,” Eagleson said. “[With] the 20-year anniversary, you get all sorts of attention on this subject … The families are literally at their wit’s end. Whether it’s Trump in office, whether it’s Obama in office, or whether it’s Biden in office, we would have sent this letter.”

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