President Bush has for the first time acknowledged the existence of secret CIA prisons holding top terror suspects and is asking Congress to approve the creation of military commissions to put them on trial. A total of 14 terror suspects have now been transferred to the U.S. naval base in Guantanamo Bay, Cuba.

In this June 26, 2006 file photo, reviewed by US military officials, a detainee holds onto a fence as a US military guard walks past at the Guantanamo Bay US Naval Base, Cuba

President Bush says one of the suspects transferred to Guantanamo Bay is Khalid Sheik Mohammed, who was number three in al-Qaida's command.

Other suspects include Abu Zubaydah, who was an alleged emissary between al-Qaida leader Osama bin Laden and many of his terrorist cells and Ramzi Binalshibh, who is thought to have been trained as one of the hijackers in the terrorist attacks of September 11, 2001.

Senior Bush administration officials say there are now no suspects in CIA detention though they intend to continue that parallel program as they say CIA interrogations have produced more than half of what U.S. officials know about al-Qaida.

In his first public admission of the previously-secret CIA prisons, President Bush told a gathering at the White House that the program has saved countless lives by disrupting terrorist plots.

President Bush delivers a speech on terrorism in the East Room of the White House

"This program has been and remains one of the most vital tools in our war against the terrorists," said Mr. Bush.  "It is invaluable to America and to our allies. Were it not for this program, our intelligence community believes that al-Qaida and its allies would have succeeded in launching another attack against the American homeland."

With the last of the current CIA prisoners turned over to the Defense Department, the president wants Congress to authorize military commissions to put them on trial.

"We put forward a bill that ensures these commissions are established in a way that protects our national security and ensures a full and fair trial for those accused," he added.  "The procedures in the bill I am sending to Congress today reflect the reality that we are a nation at war, and it is essential that we use all reliable evidence to bring these people to justice."

The U.S. Supreme Court this year ruled that military commissions are an appropriate venue for trying suspected terrorists, but they must be specifically authorized by Congress.

President Bush says he has notified the International Committee of the Red Cross (ICRC) about the transfer of the CIA detainees. He says those prisoners will now have access to the Red Cross, legal counsel and medical attention and facilities for religious worship provided at Guantanamo Bay.

The announcement came as part of a series of speeches President Bush is giving about the fight against terrorism ahead of the fifth anniversary of the September 11th attacks.

Opposition Democrats say the president is politicizing that fight in hopes of helping members of his party running for Congress in November. White House officials say the speeches are not political and are meant to keep Americans informed about a serious threat.