10,000 IS militants killed in nine months - US
More than 10,000 Islamic State fighters have been killed since an international coalition began a campaign against the group in Iraq and Syria, the US says, the BBC reports.
Deputy Secretary of State Antony Blinken told France Inter radio the coalition had seen "a lot of losses" within IS in the past nine months.
"It will end up having an impact," he added, but warned IS remained resilient and capable of taking the initiative.
He spoke after the coalition met in Paris to discuss its strategy in Iraq.
Representatives backed Iraqi Prime Minister Haider al-Abadi's plan to retake the city of Ramadi, whose capture by IS last month he described as a "failure" for the international community.
They also called for the "speedy launch" of efforts to end the conflict in Syria.
In his interview with France Inter on Wednesday, Mr Blinken insisted that the coalition campaign had not been a failure.
"There has been important progress, but equally Daesh remains very resilient and capable of taking the initiative," he said, using a pejorative term for the group based on the Arabic acronym of its former name.
Mr Blinken said IS now controlled 25% less territory in Iraq than it did when coalition air strikes began in August 2014, and that it had lost significant numbers of men and materiel.
But he also acknowledged recent setbacks, including the loss of Ramadi, where Iraqi soldiers fled their positions despite vastly outnumbering the IS force attacking them.
"At the start of this campaign [we] said it would take time," he said. "We have conceived a three-year plan and we're nine months into it."