The Bush administration took action Thursday against two Lebanese financial companies, accusing them of functioning as Hezbollah's "unofficial treasury."

The Treasury Department's action covers Bayt al-Mal and its head, Husayn al-Shami, and the Yousser Company for Finance and Investment.

As a result, Americans are forbidden from doing business with them, and any bank accounts or other financial assets belonging to these three found in the United States must be frozen.

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The department alleges that Bayt al-Mal is controlled by Hezbollah and provides financial services to the group.

Bayt al-Mal uses the Yousser Company for Finance and Investment to secure loans and to bankroll business deals for Hezbollah companies, the department said.

The companies "function as Hezbollah's unofficial treasury, holding and investing its assets and serving as intermediaries between the terrorist group and mainstream banks," said Stuart Levey, the Treasury Department's under secretary for terrorism and financial intelligence.

The U.S. calls Lebanon-based Hezbollah a terrorist group that is suspected of involvement in terrorist attacks worldwide. The U.S. also blamed Hezbollah for triggering recent bloodshed in the Middle East involving Lebanon, Israel and the terrorist organization.

The Treasury Department also alleges that al-Shami — the chief of Bayt al-Mal — is a senior Hezbollah leader. Treasury said he also has served as the head of several Hezbollah-controlled organizations, including the Islamic Resistance Support Organization — a Lebanese group that the U.S. added to its asset-blocking list last week.

Bayt al-Mal operates under the direct supervision of Hezbollah Secretary General Hasan Nasrallah, the department said. "As Hezbollah's main financial body, Bayt al-Mal serves as bank,creditor and investment arm for Hezbollah," the department said. The company's central headquarters was located in Hezbollah's stronghold in Beirut's southern suburbs, the department said.

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