But within a few weeks of the attacks, the administration blocked the assets of various charities and their supporters.
It has acted this year to block the assets of 185 of the 247 groups identified by the United States, involving millions of dollars, a Treasury official said.
Some of the senators' concerns stem from that report, but they also questioned why the office had failed to block the assets of several people designated by allies as terrorist financiers and reported by the news media.
Since the Sept. 11 attacks, the Bush administration has moved to block the assets of 153 individuals, organizations, and entities, including charities, believed to have connections to terrorist groups, a Treasury Department spokesman said.
Pakistan has cooperated with F.B.I. agents in searching for and arresting terrorism suspects and has outlawed and blocked the assets of many entities that are thought to be linked to terrorism.
Treasury Secretary Paul H. O'Neill announced that the administration had blocked the assets of 21 people with suspected links to the Basque separatist movement E.T.A., which Spanish authorities have accused of killing more than 800 people since it began a violent effort to create a Basque nation independent from Spain and France in the 1960's.
In other developments: Swiss and Austrian authorities block the assets of Viktor Yanukovych and his associates, and launch a corruption probe.
President Bush ordered the Treasury Department to block and freeze the assets of six top leaders of the militant Palestinian group Hamas and five charities that administration officials said help finance the organization.
A spokesman for the department, Tony Fratto, said in Washington, "There was coordinated action to block the assets, because this group is suspected of funding terrorist activities".
Second, the adoption of similar laws on both sides of the Atlantic to block visas and freeze the assets of those Russian officials, and their immediate families, involved or complicit in the murder of Sergei Magnitsky, the lawyer who died in jail after alleging widespread tax fraud by officials, would have a sobering effect.
