An Iraqi soldier holds an Islamic State flag during a battle with Islamic State militants, north of Mosul, Iraq.

The United States and Persian Gulf countries have agreed to collaborate to stem the flow of terrorist financing as part of a new working group, the Treasury Department said on Sunday, with the U.S. and Saudi Arabia jointly chairing the initiative.

In a memorandum of understanding that announcing the newly created Terrorist Financing Targeting Center (TFTC), the Treasury described the group as a "collaborative approach to confronting new and evolving threats arising from terrorist financing." The news comes as President Donald Trump delivers a major address to Muslims in Saudi Arabia as part of his first trip abroad.