US President Barack Obama met on Tuesday with defence ministers from 22 countries, acknowledging that he is "deeply concerned" about the advances IS is making in Iraq's Anbar province and in Syria, including the Kurdish town of Kobani. He vowed that US air strikes will continue in both countries, while saying that "important successes" have also been made in stopping IS in areas such as Erbil and Mosul.
"This is going to be a long-term campaign," Obama said without hinting at any changes in the current military strategy, which mainly involves air strikes. "There are not quick fixes involved. We are still in the early stages. As with any military effort, there will be days of progress and there are going to be periods of setbacks, but our coalition is united behind this long-term effort."
A US military official told Reuters news agency after the talks that there was an acknowledgement that IS was making some gains on the ground, despite the air strikes.
"In the short term, there are some gains that they have been able to make. In the long term, that momentum will be reversed," the official said.
Also on Tuesday, US Secretary of State John Kerry met with his Russian counterpart Sergey Lavrov in Paris, to discuss the latest developments in Iraq and Syria. Kerry said the US had agreed to "intensify intelligence cooperation with respect to IS and other counter-terrorism challenges of the region".
He said Moscow would also explore whether it could do more to help arm and train Iraq's embattled military. However, Kerry stopped short of saying that Moscow would join the US-led international coalition against IS.
The US and Russia have common ground in their concern about fighters from their countries joining IS, and then returning to carry out attacks at home.
"There may be as many as 500 or more from Russia," Kerry said. These include fighters from Russia's predominantly Muslim North Caucasus, a region where armed rebels have waged daily violence to establish an Islamic state.