Kentucky Sen. Rand Paul (R) on Tuesday rejected a White House offer to let senators read a federal court nominee's memo authorizing a drone strike on a U.S. citizen, calling anything short of a full public release "inadequate."

Paul is threatening to block the federal appeals court nomination of David Barron, who wrote a Justice Department memo justifying a drone strike against alleged al Qaeda commander Anwar al-Awlaki, until that memo is released. Last month the 2nd U.S. Circuit Court of Appeals ordered the government to release the document.

"A federal court has ordered the public release of a redacted legal memo authored by Barron and I believe that anything short of that is inadequate," Paul said in a statement released Tuesday. "I will continue to oppose this nomination until the document is released."

Barron's nomination has been approved by the Senate Judiciary Committee. It's not clear whether Paul will be able to stop Senate Majority Leader Harry Reid (D-Nev.) from bringing Barron's nomination to a full Senate floor vote.

President Barack Obama's administration had offered earlier Tuesday to let senators read the memo before they vote on Barron's nomination. But that offer has mollified neither Paul nor the American Civil Liberties Union, which wants senators to be able to review any and all of the memos Barron may have written justifying the targeted killing program -- not just the memo the 2nd Circuit publicly ordered to be released. (Part of the 2nd Circuit's order was kept under seal, so it may have ordered the release of additional Barron memos.)

Last year Paul mounted a 13-hour filibuster against the nomination of John Brennan to head the CIA over concerns about the drone program.

Barron served as the acting head of the Justice Department's Office of Legal Counsel from 2009 to 2010. The office's legal memos, underlying the targeted killing program, have been the subject of several contentious legal battles over whether they will be publicly released.

During Tuesday's White House briefing, press secretary Jay Carney called Barron, a Harvard Law professor, an "exceptionally qualified judicial nominee" for a spot on the 1st U.S. Circuit Court of Appeals in Boston.

"I can confirm the administration is working to ensure that any remaining questions members of the Senate have about Mr. Barron's legal work at the DOJ are addressed, including making available in a classified setting a copy of the al-Awlaki opinion to any senator who wishes to review it prior to Mr. Barron's confirmation vote," Carney said. "In his committee vote, Mr. Barron received unanimous Democratic support."