WASHINGTON - The commission investigating the September 11 attacks feels unanimously that White House national security adviser Condoleezza Rice should testify in public and under oath when she appears before the panel a second time, the chairman said on Sunday.

Rice has refused to appear before the independent panel in public and under oath to answer allegations from former White House counter-terrorism official Richard Clarke that the Bush administration neglected the threat from al Qaeda. The White House has asked for a second private session for Rice.

The commission's Republican chairman, former New Jersey Gov. Tom Kean, told US television on Sunday his panel would continue to press for Rice to appear publicly but would not try to force her to do so under a court order.


"To get into a court battle over a subpoena we don't think is really appropriate right now, nor will it help us," Kean said.

"We are still going to press and still believe unanimously as a commission that we should hear from her in public."

Asked on TV whether they believed the White House might relent, commission vice chairman, former US Rep. Lee Hamilton, said, "We're going to keep trying."

"We would like it under oath, because we ask witnesses to appear under oath," Kean added. "That's up to her. We will ask her to take the oath."

Rice, once Clarke's White House superior, has led furious administration denials of his charges and was slated to appear on US television later on Sunday.

The administration says Rice testifying publicly would set a precedent that other presidential advisers could be compelled to testify about advice they have given the president.

"We think in a tragedy of this magnitude that those kind of legal arguments are probably overridden," Kean said.

US Rep. Chris Shays, a Connecticut Republican, said, "It's been one of the stupidest things this White House has done. ... She has to testify."

But on television US Secretary of State Colin Powell said a legitimate "presidential authority problem" was involved.

"I wouldn't have done it during the time I was there working for President Reagan," Powell said of his own tenure as national security adviser. "The president has to have a unique and confidential and private relationship with his immediate staff."

Powell also said he believed Rice was being unfairly criticised by Clarke for the administration's response to the threat from al Qaeda before the September 11, 2001, attacks that killed nearly 3000 in New York and outside Washington.

"I think Dr. Rice is getting a bit of a bum rap. It's being set up as 'Condi, I told you everything that you needed to do,' and she ignored it all. That's not accurate," he said.

Both Powell and Defence Secretary Donald Rumsfeld noted that none of Clarke's recommendations for combating al Qaeda in Afghanistan could have prevented the domestic attacks.

"The terrorists were in the United States. They used a US aeroplane, and they attacked a US target," Rumsfeld told a Sunday TV news programme.

Democratic presidential candidate John Kerry has challenged Rice to appear publicly, accusing US President George W Bush's White House of stonewalling the commission and of attempting "character assassination" against Clarke, who has served four US presidents.

To buttress his contentions, Clarke on Sunday urged that all related information be made public, including previous testimony of his on Capitol Hill, which Republicans are challenging, as well as Rice's testimony before the 9/11 commission and all memos and e-mail between them.

"Let's declassify all of it," Clarke said on US television.

The White House said it has asked the CIA to review whether Clarke's 2002 testimony should be declassified.

Hamilton, an Indiana Democrat, said they did not yet have a date for interviewing Bush or Vice President Dick Cheney. Bush is insisting on testifying privately before only Kean and Hamilton, though he has relented on appearing for only an hour.