President Barack Obama says he believes Russia will ultimately recognize that the Islamic State group poses a bigger threat to Russia than opposition groups fighting Syrian President Bashar Assad.

Obama is speaking at a news conference in Paris a day after meeting with Putin. He says the U.S. and Russia remain at odds over whether Assad can be part of Syria's future government.

Obama says he doesn't expect Russia to change course overnight and stop targeting opposition groups with airstrikes. He says Russia has invested for years in keeping Assad in power.

But Obama says it's possible over the coming months that the U.S. will see a "shift in calculations" by Russia and a recognition that it's time to end Syria's civil war.