Russia and the United States will hold more talks on air safety over Syria - to try to avoid accidental clashes during their separate bombing campaigns.
The Pentagon says at least one American jet has had to change course to avoid an incident.
Meanwhile, America is halting a programme to create a rebel force in the country after admitting it has largely failed.
It has spent over half a billion dollars on the project.
The US Department of Defense says it will instead provide equipment packages and weapons to a "select group of vetted leaders and their units" so they can push into Islamic State controlled territory.
Defense Secretary Ash Carter said he remains “convinced that a lasting defeat of ISIL in Syria will depend in part on the success of local, motivated and capable ground forces.”
"I believe the changes we are instituting today will, over time, increase the combat power of counter-ISIL forces in Syria and ultimately help our campaign achieve a lasting defeat of ISIL," he added,
John Kirby is a US State Department spokesperson:
