President Bush is defending his decision to authorize military tribunals to try non-U.S. citizens accused of terrorism. Civil liberties groups have attacked the plan. Meanwhile, congressional critics of the administration's anti-terror tactics at home intend to closely question Attorney General John Ashcroft when he appears before a Senate committee next week.

At the White House Monday, President Bush said he is not the least bit concerned that some U.S. allies are expressing reservations about his plans to use military tribunals to prosecute non-Americans accused of terrorism.

"It makes eminent sense to have the military tribunal option available," he said. "It makes sense for national security purposes. It makes sense for the protection of potential jurors. It makes sense for homeland security. It is the right decision to make and I will explain that to any leader who asks."

The president was responding to a question about Spain's decision not to extradite a group of suspected al-Qaida members unless the United States promises that they will not face either the death penalty or trial in a military court.

On Sunday, a key opposition Democrat in the Senate also expressed concern about the use of military tribunals. Senator Patrick Leahy, chairman of the Senate Judiciary Committee, spoke on NBC's Meet the Press.

"When we are talking about setting aside, largely setting aside our criminal justice system for something like this, we end up looking to the people we have asked to be our allies more and more like some of the things we are fighting against," he said. "I don't think we should be doing that."

But there are plenty of supporters for the idea of using military tribunals to try non-citizens accused of terrorism as well.

Senator Richard Shelby is the top Republican on the Senate Intelligence Committee. He says extraordinary times call for extraordinary measures. But Senator Shelby is critical of the administration's decision to monitor phone calls between terror suspects arrested or detained since September 11 and their lawyers. He also was interviewed on NBC.

"Yeah, that concerns me a little bit because I practiced law sixteen years and that has been a privilege that has a very important precedent for it, the courts have upheld it and I think we ought to keep it," he said.

U.S Attorney General John Ashcroft is scheduled to testify before the Senate Judiciary Committee next week.

Senator Leahy has suggested that Mr. Ashcroft set aside several hours to answer questions from lawmakers on a range of issues related to the domestic crackdown on suspected terrorists in the wake of the September 11 attacks.

At a Washington news conference Monday, Attorney General Ashcroft defended the administration's anti-terrorism efforts. "With a strategy of deliberate terrorist disruption, with tighter security around potential targets in America and with arrests and detentions that have made America grow stronger, not weaker," he said.

Mr. Ashcroft says the Justice Department will release new information later this week about the more than 1,000 people arrested or detained in the wake of the September 11 terrorist attacks.