ASHINGTON, Sept. 24 ・President Bush ordered an immediate freeze today of all assets in the United States of suspected Islamic terrorist groups and individuals and gave the treasury secretary broad new powers to impose sanctions on banks around the world that provide them access to the international financial system.

Announcing his executive order this morning in the Rose Garden, Mr. Bush reached beyond American borders and said that any foreign banks that did not cooperate with American investigators could be cut off from doing business in the United States.

Mr. Bush's plan to punish foreign financial institutions that handle terrorists' money echoes his threat to other nations that harbor terrorists: if the banks choose to harbor terrorists' money, they will be treated as hostile entities.

"We're putting banks and financial institutions around the world on notice," Mr. Bush said. "We will work with their governments, ask them to freeze or block terrorists' ability to access funds in foreign accounts. If they fail to help us by sharing information or freezing accounts, the Treasury Department now has the authority to freeze their banks' assets and transactions in the United States."

In effect, a foreign bank that refused to cooperate would find itself unable to operate in the United States.

Among the 27 individuals and organizations on a list attached to the order were three charities that the government believes knowingly or unwittingly channeled money to Osama bin Laden and his Al Qaeda network. The groups were Makhtab al-Khidamat, the Wafa Humanitarian Organization and the Al Rashid Trust. [Page B4.]

"Money is the lifeblood of terrorist operations," Mr. Bush said.

"Today, we're asking the world to stop payment," Mr. Bush said, calling the move "a major thrust of our war on terrorism."

Officials said the listed groups were the most prominent with identified links to Al Qaeda.

But there are questions about what the president can expect with the financial crackdown. The demand that overseas banks release information about accounts reportedly controlled by terror groups could run afoul of domestic confidentiality laws. Past attempts to crack down on the assets of terrorists and drug lords have had just limited success.

In 1998, President Bill Clinton issued an executive order that sought to freeze the assets of Mr. bin Laden and Al Qaeda, though it did not include many of the other organizations linked to Al Qaeda that were on the list today. Moreover, Mr. Clinton's administration never openly threatened sanctions against countries and overseas financial institutions that did not join a crackdown.

Of the groups or individuals cited today, one-third had been previously identified by the United States in connection with terrorism. The others were new.

One difficulty in using such economic sanctions against terrorism is that the amounts of money used to conduct terrorist activities may be a few drops in the trillion-dollar torrent that rushes through the world financial system each day.

The bombing of the World Trade Center in 1993 cost an estimated $20,000, and the F.B.I. has said it believes that the attacks on Sept. 11 were conducted for $200,000 in training, airfare and living expenses.

Mr. Bush declined to talk about the evidence behind his list. He said it was based on "clear evidence, much of which is classified."

The White House refused to discuss what it knew about the links between the charities, for example, and Al Qaeda. Mr. Bush deflected calls for details, insisting that "we will not jeopardize the sources."

"We will not make the war more difficult to win by publicly disclosing classified information," he said.

But White House officials acknowledged that they did not believe that Mr. bin Laden maintained significant assets in the United States and that they did not have a clear idea how his activities were financed.

The Clinton administration began tracing funds to Mr. bin Laden and Al Qaeda in 1998. That effort did not locate any assets held here.

Mr. Bush said his order was much more sweeping. He cited a number of related groups operating in places like Egypt, the Philippines, Somalia and Yemen.

Two of the proscribed groups are generally believed to have ties to Pakistan. An Islamic militant group, Haraka Ul Mujahidin, is based in Pakistan, and it is widely believed to conduct terrorist activities against India in Kashmir.

Several groups, including Abu Sayyaf of the Philippines, the Armed Islamic Group of Algeria and Al Jihad of Egypt, are well-known Islamic militant organizations that the State Department had already classified as terrorist groups, meaning that the Treasury Department should already have taken action to seize their assets.

Other new targets appear to be suspected associates of Mr. bin Laden. Two, Tariq Anwar al-Sayyid Ahmad and Tharwat Salah Shihatah, have been sentenced to death in Egypt for plotting to overthrow the Egyptian government, according to Middle East news reports.

Mr. Bush is betting that by giving Treasury Secretary Paul H. O'Neill the power to shut out foreign banks from the American market, he can force cooperation. Under the wording in the order, Mr. O'Neill can act against terrorists' associates, as well as financial intermediaries, even if it is not possible to prove complicity. Under the order, if a bank's offices and equipment are used by terrorists, the United States could seize the bank's assets in this country.

The treasury secretary already has the power to impose penalties on domestic and foreign banks that do business with Colombian drug cartels. But the secretary has not had the authority to threaten banks with similar sanctions if they provide services to terrorists.

Although it seems highly unlikely that Western banks or even secretive offshore financial centers would willingly provide services to terrorists, the new order could pressure banks around the Persian Gulf elsewhere in the Middle East to guard against even unwitting terrorist ties for fear of losing access to the international system.

It is unclear how much money the order will affect. The Treasury Department gave no estimates. In all likelihood, Mr. bin Laden's organization has kept its funds in places that are as difficult to find as the reclusive terrorist himself.

French and Swiss officials said they were acting against suspected terrorist financiers who operated in those countries. The European Commission directed its finance, justice and interior ministers to stop financing terrorist activities, though it was not clear whether Europe would immediately focus on the 27 groups and individuals listed here.

As Mr. Bush focused on the financial war, the Pentagon nearly completed its deployment of roughly 50 bombers and surveillance aircraft, including U-2's from Beale Air Force Base in California and RC-135's from Offutt Air Force Base in Nebraska, to within easy striking distance of Afghanistan, military officials said today. Many of the planes are at a field on Diego Garcia, the British island in the Indian Ocean.