President Barack Obama said Wednesday that if Russia shifts its military strategy in Syria to focus on Islamic State, the U.S. would welcome cooperation with Moscow on an intensified military campaign. He said he conveyed that message to Russian President Vladimir Putin in a meeting in Turkey earlier this week…

Mr. Hollande telephoned his Russian counterpart Tuesday to discuss possible joint plans, and made arrangements to visit Washington and Moscow next week to pursue the formation of a major new alliance. France launched a third round of airstrikes Tuesday night against Islamic State’s de facto capital of Raqqa, Syria, while waves of Russian warplanes and cruise missiles struck the same area in the daytime.

The effort could yet dissolve, as major problems—especially the legacy of Russia’s involvement in Ukraine and discord over Syria’s future—haven’t gone away. The involvement of Arab allies with overlapping and uneven agendas complicates regional diplomacy.

But among the signs of potential progress, Russia gave Washington advance notice of its airstrikes Tuesday—the first time it had done so since the Russian bombing campaign started Sept. 30. U.S. officials said Russia conducted between 12 and 20 strikes Tuesday—some cruise missiles from Russian ships and some strikes by TU-22 backfire bombers.