WASHINGTON — The chairman of a House committee investigating the deadly 2012 attacks in Benghazi said Wednesday he wants an independent review of Hillary Rodham Clinton's email server that she insists should remain private, setting up a confrontation between the GOP-led Congress and the likely presidential candidate.

House Speaker John Boehner's office did not rule out a vote in the full House to force Clinton to turn over the server.

Rep. Trey Gowdy, R-S.C., told the Associated Press that neither Clinton nor the committee should determine which emails are made public and which remain private.

"Let a neutral, detached, disinterested observer make that call," he said, suggesting a retired judge or inspector general could fill the role.

If Clinton rebuffs the committee, the issue could escalate with a possible House vote on a subpoena.

"We are not ruling out any options at this point," said Michael Steel, a spokesman for Boehner. "Secretary Clinton must turn over the server to a neutral arbiter who can inventory the records, make a complete, thorough accounting and impartial determination" of which emails are public and which are private.

Steel called Clinton's contention that the server should remain private "unacceptable and unsustainable."

Gowdy's committee has issued a subpoena for Clinton's emails and other documents related to the attacks in Benghazi, Libya, but Gowdy said Wednesday that the panel does not have the authority to issue a subpoena for the server.

Despite the threat of a House vote on a subpoena, Gowdy said he hopes Clinton will turn over the server voluntarily.

Clinton said at a news conference Tuesday that all her work-related email would be made public, but acknowledged that she deleted thousands of messages related to personal matters. Clinton said the server "will remain private."

Gowdy challenged that idea. "You don't get to grade your own papers in life," he said. "You don't get to determine what's personal and what's public."

While some emails are likely to remain personal, Gowdy said he wants to ensure that any related to Libya or the Benghazi attacks is made available to the committee.