The U.S. is fighting ISIS with sanctions.
On Tuesday, the U.S. Treasury Department added 25 individuals to a counterterrorism sanctions list.
Nationals on the list are from countries like Libya, Yemen, Saudi Arabia, Russia, the U.K., Indonesia, Tunisia and France.
Also added were four ISIS-related organizations, including terrorist groups in Algeria, Indonesia, Afghanistan and Pakistan.
The sanctions effectively freeze any property within the U.S. which belongs those on the list. Any transactions between them and U.S. entities is also prohibited.
President Obama spoke about fighting ISIS at Tuesday's counterterrorism summit.
"Now I have repeatedly said that our approach will take time. This is not an easy task. ... This is not a conventional battle, this is a long-term campaign not only against this particular network but against their ideology," he said.
The United Nations also sanctioned four Britons on Tuesday for the first time. The British government made the request on the grounds the four were active recruiters for ISIS.