A top Obama administration official says the Islamic State group's ranks of foreign fighters have dropped to about 25,000 from a peak of 35,000.
Brett McGurk is the US special envoy for the global coalition to counter IS.
He says fighters from 120 countries have joined the group.
McGurk is touting progress in the US-led effort to defeat IS.
He says the extremist group is under pressure and has cut fighters' salaries by about half.
McGurk says President Barack Obama will get an update on diplomatic and political efforts Thursday at the State Department.
The meeting comes after the US and Russia announced a cease-fire agreement for Syria to take effect later this week. McGurk says the U.S. Is under no illusions about how difficult implementing the cease-fire will be.
