The House and Senate Intelligence Committees each held a second day of closed-door hearings amid charges by some Democrats that the White House lied or had exaggerated the danger to bolster its case for invading Iraq.

In the weeks before the conflict, US President George W. Bush and senior administration officials asserted that Iraqi dictator Saddam Hussein possessed chemical and biological weapons and was developing nuclear arms.

But several weeks after the end of hostilities, US and British forces on the ground in Iraq have yet to find any evidence to support those claims.

Although both chambers of the US legislature are holding hearings on the matter, they have taken very different approaches in reviewing possible US intelligence lapses.

In the House of Representatives, Intelligence Committee Chairman Porter Goss took a largely collegial approach, working closely with the panel's top Democrat, Jane Harman, in structuring this week's hearings and calling senior intelligence officials before the committee.

Goss, a Republican and a former Central Intelligence Agency officer, has also left open the possibility of holding public hearings once the closed-door hearings end.

His committee plans to meet with top intelligence and administration officials and to produce an unclassified summary report at the end of the hearings.

The tone has been much more rancorous in the Senate, with Intelligence Committee chairman Pat Roberts refusing to heed Democrats' calls for a formal investigation, which he says would politicize the process.

"Calls for a formal investigation into this matter are premature. The committee is aware that the search for (weapons of mass destruction) will continue for the foreseeable future. This crucial work should be allowed to proceed unimpeded," Roberts said in a statement.

"The results of this search will become an integral part of the factual record and they are essential if the committee is to reach any informed conclusions," the Kansas Republican said.

Senate Democrats have also made the case that witnesses, including intelligence and administration officials, must be called during the hearings, while Roberts is insisting for now, upon hearings that are primarily a review of CIA transcripts and other documents.

On Thursday, Daschle criticized Robert's more cautious approach.

"I think the House in this case has set a much better standard. They've done it right. They've done it on a completely bipartisan basis ... and they're doing it aggressively," he said.

"I think it is important for them to be bipartisan. I think it is important for us to be thorough," Daschle said.

"The American people have a right to know, and the sooner we can do that ... the better off the country's going to be," he said.

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