The U.N. Security Council Thursday unanimously passed the first-ever resolution ordering members to enforce laws against terror financing.
Experts believe as many as two-thirds of U.N. members are not adequately prosecuting those who aid terrorists in acquiring money.
Thursday's resolution demands all states "ensure that their domestic laws and regulations establish serious criminal offenses" to collect funds or financial resources to terrorist groups or individual criminals.
It also calls on members to create financial intelligence units.
Nations that fail to carry out the resolution would face U.N. sanctions.
U.N. counterterrorism chief Vladimir Voronkov said the resolution comes at a "critical time," saying terrorists have gotten their hands on cash through both illegal and legal channels, including drug trafficking, the construction trade and used car sales.
The U.N. resolution would also urge members to stop paying ransom to kidnappers, saying such payments have become a major source of financing for Islamic State and others.