The Bush administration, widening its financial assault on global terrorism, on Monday blocked assets of an Islamic charity's branches in Bosnia and Somalia.

Treasury Secretary Paul O'Neill said the action was being taken jointly with the government of Saudi Arabia and underscores growing international cooperation among countries to cut terrorists off from their sources of funding.

"We take a new step in the war on terrorist financing, making our first joint designation of a financial supporter of terrorism," O'Neill said. "This joint designation marks a new level of coordination in the international cooperation that has characterized the fight against international terrorism to date," he added.

O'Neill said the U.S. government has evidence that some money from the Al-Haramain Islamic Foundation's offices in Bosnia and Somalia had been diverted to support terrorist activities, but he wouldn't provide further details.

The Treasury Department's action targets only the foundation's branches in those two countries. The charity is based in Riyadh, Saudi Arabia, and has offices in more than 50 countries, according to information on the group's Web site.

The group, according to its Web site, uses donations for many activities, including educating people about Islamic doctrines, providing medical aid and food to some countries and financing the building of schools, mosques and other projects. The site says nothing about providing weapons or cash and does not advocate violence.

A message, seeking comment, was left with a U.S. contact for the group.

The Treasury Department said the charity's office in Somali "is linked to Usama bin Laden's Al Qaeda terrorist network and to Al-Itihaad al-Islamiya, a Somali terrorist group" and the Bosnia office "is linked to Al-Gama'at Al-Islamiyya, an Egyptian terrorist group."

The new blocking action follows O'Neill's tour of the Middle East last week in which separating terrorists from their financing was a key topic in his meetings. Continued international cooperation is crucial to the U.S. financial war on terrorism. While the United States can block assets found inside the country, it depends on other countries to act against targeted groups outside U.S. borders.

The blocking came six months after the terrorist attacks in New York and Washington.

More than $104 million in financial assets linked to Al Qaeda and Afghanistan's former ruling Taliban militia have been blocked worldwide since Sept. 11. The United States has identified 191 individuals and organizations suspected of financing or engaging in terrorism and wants their assets frozen.

The blocking action was posted on the Web site of Treasury's Office of Foreign Assets Control, which has primary responsibility for carrying out the orders.

O'Neill said it was too early to know whether the charity's branches in Bosnia and Somalia have any financial assets in the United States. Al-Haramain was among six Islamic charities banned in Kenya in 1998 on suspicion of involvement in the bomb attack on the U.S. Embassy in Nairobi.