“President Barack Hussein Obama kept 33 million pages of documents, much of them classified,” Mr. Trump said in a statement. “How many of them pertained to nuclear? Word is, lots!”

But the National Archives and Records Administration, or NARA, which preserves and maintains records after a president leaves office, confirmed on Friday afternoon that Mr. Obama had not kept his documents — classified and unclassified — as required under the Presidential Records Act of 1978.

The National Archives “assumed exclusive legal and physical custody of Obama presidential records when President Barack Obama left office in 2017, in accordance with the Presidential Records Act,” the statement said. “NARA moved approximately 30 million pages of unclassified records to a NARA facility in the Chicago area, where they are maintained exclusively by NARA. Additionally, NARA maintains the classified Obama presidential records in a NARA facility in the Washington, D.C., area.”