National Security Agency critics expecting to testify before an ad hoc House panel will have to take a back seat on Wednesday due to a scheduling conflict with President Obama.

President Obama scheduled a meeting with the House Democratic Caucus Wednesday, forcing Florida Democratic Rep. Alan Grayson to reschedule a bipartisan hearing during which journalist Glenn Greenwald was expected to testify on the NSA’s bulk spying program, Politico reports.

Greenwald — who was expected to testify via satellite link — was scheduled to appear alongside Julian Sanchez of the Cato Institute and American Civil Liberties Union Legislative Counsel Michelle Richards.

Greenwald, Sanchez and the ACLU have been openly critical of the program, disclosed to the public by former NSA contractor Edward Snowden. Grayson intended the hearing to be an opportunity for critics of the program to publicly air their concerns before Congress.

“Unfortunately we are rescheduling,” Lauren Doney, Grayson’s spokesman, told The Daily Caller.

“We didn’t anticipate the meeting with President Obama, so we’re trying to see what our options are now,” said Doney.

Doney told The Daily Caller Tuesday evening that he did not think a topic for the meeting had been announced.

Sanchez told The Daily Caller via direct message on Twitter that the hearing was postponed and that “they’ll probably end up doing it in Sept.”

The White House Press Office did not respond to The Daily Caller’s request for comment by the time of publication.

The Senate Judiciary Committee is scheduled to hold its own hearing about the U.S. Intelligence communities authorities under Foreign Intelligence Surveillance Act and the Foreign Intelligence Surveillance Court Wednesday morning.

When asked about whether Chairman Patrick Leahy is considering inviting Greenwald, Sanchez, or any of the NSA whistleblowers, to testify as additional witnesses or to testify at another hearing, Leahy’s Judiciary Committee spokesperson Jessica Brady offered no additional information.

Brady told the The Daily Caller, “[T]he chairman has scheduled a hearing and we have two panels of witnesses.”

U.S. intelligence agencies, Reuters reports, are expected to declassify documents related to Snowden’s disclosures this week.

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