CNN  — 

President Joe Biden said Tuesday that he did not know that government records from his time as vice president, which included some classified documents, had been taken to his private office after he had left public service.

“I was surprised to learn there were any government records that were taken there to that office,” Biden said in response to a reporter’s question at a news conference in Mexico City, where he was attending a trilateral summit with the leaders of Mexico and Canada.

Biden emphasized that he does not know what is in the documents that were found at a Washington, DC office that he used when he was an honorary professor at the University of Pennsylvania. CNN reported earlier in the day that Biden and his White House legal team do not know what’s precisely contained in the classified documents because they did not review them, according to two sources familiar with the matter.

CNN reported Tuesday that among the classified documents are US intelligence memos and briefing materials that covered topics including Ukraine, Iran and the United Kingdom, according to a separate source familiar with the matter.

Biden didn’t know the documents were there, and didn’t become aware they were there, until his personal lawyers informed the White House counsel’s office, one source familiar with the matter told CNN. In explaining why Biden doesn’t know what’s in the documents, the source said the president’s team is wary of appearing to interfere given the Justice Department is still scrutinizing the matter.

The president’s personal attorneys found the documents in November when packing files, the White House has said, and then the counsel’s office notified the National Archives and Records Administration. Biden’s lawyers provided the documents to the National Archives the day after they found them and are still cooperating in the matter being reviewed by the US attorney in Chicago, according to the White House.

The president said his attorneys “did what they should have done” by immediately calling the Archives.

“People know I take classified documents, classified information seriously,” Biden added, saying that the documents were found in “a box, locked cabinet – or at least a closet.”

Fewer than a dozen classified documents were found at the office, another source told CNN. It is unclear why they were taken to Biden’s private office. The classified materials included some top-secret files with the “sensitive compartmented information” designation, also known as SCI, which is used for highly sensitive information obtained from intelligence sources. Federal officeholders are required by law to relinquish official documents and classified records when their government service ends.

In response to specific questions about why the Biden team did not disclose the discovery of classified documents in November at Biden’s private office, Ian Sams, a spokesman for the White House counsel’s office, said that they are “limited in what we can say” now because the Justice Department is looking into the matter, and “further details” may be shared in the future.

“This is an ongoing process under review by DOJ, so we are going to be limited in what we can say at this time. But we are committed to doing this the right way, and we will provide further details when and as appropriate,” Sams said in a statement Tuesday afternoon.

White House downplays documents

The White House has convened a call with top allies to explain the investigation surrounding the classified documents, hoping to quell the growing criticism and questions about the discovery.

A White House official characterized the documents as “fewer than a dozen,” two people familiar with the call say, none of which are “particularly sensitive” and “not of high interest to the intelligence community.”

No written talking points were sent to administration allies – as is often the cases during an unfolding political crisis or key moment – but the call was intended to amplify the explanation released Monday night by the White House.

On the call, a top official reiterated how the president’s counsel notified NARA immediately.

The White House is still determining how much they can – and choose to – say about these documents, given the investigation and sensitivity. This was known to only a remarkably tight circle until news reports on Monday, aides say.

Biden tries to stay focused on summit

As the news of the classified documents quickly consumed coverage back at home, Biden was busy kicking off a highly anticipated bilateral meeting with Mexican President Andres Manuel Lopez Obrador, where immigration was expected to be among the top issues discussed.

As the moment was unfolding, one senior administration official traveling with the president told CNN that Biden had been in meetings all afternoon ahead of the extended bilateral meeting with his counterpart.

“Nothing has changed in his schedule,” the official said. “He’s focused on the summit and meeting with our closest neighbors.”

On whether advisers have discussed the issue of the classified documents during Biden’s visit to Mexico so far, this official said that as far as they were aware, it had not come up.

Seated to Biden’s left during his meeting with the Mexican president was Attorney General Merrick Garland, who has asked the US attorney in Chicago to review the matter, a source familiar with the matter told CNN, a process that is still in a preliminary stage.

The US attorney in Chicago, John Lausch Jr., was appointed by former President Donald Trump in 2017. Garland chose to have Lausch conduct the Biden documents investigation because he is one of two remaining Trump-appointed US attorneys and thus avoids the appearance of a conflict of interest because he wasn’t appointed by Biden, people briefed on the matter said.

Lausch has already completed the initial part of his inquiry, a source familiar with his work told CNN. He has provided his preliminary findings to Garland, the source said.

That means Garland now faces a critical decision on how to proceed, including whether to open a full-blown criminal investigation. Garland was also personally involved in some of the key decision-making related to the Trump documents investigation and the decision to send the FBI to search Mar-a-Lago.

A stark contrast between investigations into Trump and Biden

The episode has echoes of the scandal that enveloped Trump in late 2021 over scores of classified documents found at his Mar-a-Lago home in Florida during a raid by the FBI. However, there are some key differences between the two scenarios in the Biden team’s telling.

Sauber said Biden’s personal attorneys quickly turned over a small number of classified documents once they were found in a locked space. With Trump, when the National Archives realized key records were missing it was forced to haggle with Trump for months over the return of government documents.

The documents discovered in Biden’s office had never been sought or requested by NARA or any other government entity.

Trump eventually gave 15 boxes of materials back to NARA. But federal investigators later came to correctly suspect that he was still holding onto dozens of additional classified files. So, DOJ prosecutors secured a grand jury subpoena and later got a judge’s permission to search Mar-a-Lago, to find the documents. He is now under investigation by special counsel Jack Smith for potentially mishandling classified documents.

Ever since the FBI searched Mar-a-Lago in August – a search that uncovered dozens of additional classified files – Trump has promoted wild and unfounded allegations about his predecessors’ supposed mishandling of government records. The news about classified records turning up at Biden’s private office is sure to provide new fodder to Trump, who has already announced his 2024 presidential bid.

Trump’s lawyers see the revelation of the documents in Biden’s private office as a huge asset to their ongoing case related to his handling of classified documents after he left office, believing it showcases how easy it is to unknowingly take documents that are supposed to be in the possession of the federal government.

While the differences in the two incidents are stark, given Trump resisted turning over the documents he took, his team plans to highlight how these documents were found days before the midterm election but nothing was said publicly about it.

Republicans pledge to investigate

The news has quickly become a flashpoint on Capitol Hill for House Republicans eager to use their new oversight powers on the Biden administration.

Rep. James Comer, who chairs the House Oversight Committee, told CNN he plans to press the National Archives, which his committee oversees, for information about the classified documents.

“President Biden has been very critical of President Trump mistakenly taking classified documents to the residence or wherever and now it seems he may have done the same,” Comer said. “How ironic.”

The Kentucky Republican sent letters to the Archives and the White House Counsel’s Office Tuesday night. He requested that documents and other information be turned over no later than January 24 and that NARA General Counsel Gary Stern and NARA Director of Congressional Affairs John Hamilton be made available for transcribed interviews with committee staff no later than January 17.

House Speaker Kevin McCarthy didn’t say whether he believes House Republicans should investigate Biden’s retention of classified documents but said the reaction to Trump holding onto classified documents has been driven by politics.

“I just think it goes to prove what they tried to do to President Trump overplayed their hand on that,” McCarthy said.

“They’ve been around even longer,” McCarthy said of Biden’s team. “President Trump had never been in office before and had just left, came out. Here’s an individual spent his last 40 years in office.”

McCarthy added: “It just shows that they were trying to be political with President Trump.”

Rep. Jamie Raskin, the top Democrat on the House Oversight panel, pointed to what the Biden team detailed as key differences between the two instances, noting Biden’s attorneys “appear to have taken immediate and proper action to notify the National Archives about their discovery of a small handful of classified documents found in a locked cabinet at the Penn Biden Center so they could be returned to federal government custody.”

Still, some members of Biden’s own party also expressed concern at the idea of classified documents being found in an improper location.

Two senior Democrats on the House Intelligence Committee – Reps. Adam Schiff and Jim Himes – both told CNN that classified documents must be handled securely, offering their first reaction to news that President Biden may have mishandled classified documents from his time as vice president.

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Sen. Mark Warner, the Democratic chairman of the Senate Intelligence Committee, said on Tuesday he expects to be briefed on the classified documents.

“Our system of classification exists in order to protect our most important national security secrets, and we expect to be briefed on what happened both at Mar-a-Lago and at the Biden office as part of our constitutional oversight obligations,” Warner said in a statement, referring to a pending briefing that the committee is also expected to receive on Trump’s retention of classified documents.

The new GOP chairman of the House Intelligence Committee, Rep. Mike Turner, has sent a letter to Director of National Intelligence Avril Haines requesting an “immediate review and damage assessment” of the classified documents. Members of the House Intelligence Committee sent Haines a similar request after classified documents were recovered from Trump’s Mar-a-Lago estate.

This story has been updated with additional reporting.

CNN’s Manu Raju, Sara Murray, Zachary Cohen, Annie Grayer, Jamie Gangel, Marshall Cohen and Evan Perez contributed to this report.