The number of foreign militants fighting for the Islamic State has dropped from a peak of 35,000 to around 25,000, a top official of the United States administration said. Brett McGurk, who is the US special envoy for the global coalition to combat ISIS, said fighters from 120 countries have joined the terror group.

McGurk highlighted the progress made by the US-led coalition to defeat IS and said that being under pressure, the extremist group had reduced its fighters’ salaries by about half. President Barack Obama will be updated on diplomatic and political efforts on Thursday at the State Department, he said. This meeting comes after the Syrian government agreed to a ceasefire deal on Tuesday announced by the United States and Russia the day before. The agreement will take effect later this week. McGurk, however, admitted that the US was aware of how difficult it will be to implement the ceasefire.