On Tuesday, U.S. government officials announced sanctions against 25 people and groups affiliated with the Islamic State. The announcement has revealed that the Islamic terrorist organization has connections in Europe, Asia, and the Middle East.

The financial sanctions were placed in hopes of interrupting the Islamic State’s financial, logistical, and recruiting operatives who are not suitable targets for drone strikes. Many of the ISIS affiliates operate outside of the war in Iraq and Syria. U.S. officials also hope that the sanctions prevent ISIS fighters from getting supplies and travelling.

The Treasury Department’s sanctions were forced on Islamic State officials who operate in Pakistan, Libya, Yemen, Afghanistan, and Tunisia. Individuals who were sanctioned included was a British national Aqsa Mahmood. Mahmood is accused of recruiting three young British school girls to leave the United Kingdom and become wives of ISIS fighters in February. It is believed that her location is in Syria.

Government officials also reported that the Islamic State’s biggest money-maker is oil sales, taxation, and extortion, which won’t be affected by the sanctions. Daniel Glaser, the Treasury’s assistant secretary for terrorist financing, said that ISIS is making as much as $500 million per year from oil sales, which is beyond their estimated payroll of $360 million a year. Experts are also skeptical of the effectiveness of the sanctions given the extensive smuggling networks in the region.

U.S. President Barack Obama and other world leaders recently discussed the battle against the Islamic State during the address at the General Assembly.

“This is not a conventional battle. This is a long-term campaign — not only against this particular network, but against its ideology,” Obama said.

World leaders still have not come to an overall agreement on how to eradicate ISIS.