Turkey said it would allow Iraqi Kurds passage to Syria, and the U.S. dropped weapons and aid to Kobane, where Kurdish fighters have been battling the Islamic State.
The Syrian town along the Turkish border has become, for now, the epicenter of the fight.
The Turkish attacks underscore the regional spillover from the campaign against the Islamic State.
But Turkish officials said talks are continuing to let the U.S. use Incirlik Air Base against the Islamic State.
Fighters say they repelled latest assault by Islamic State forces in battle for control of Syrian town.
U.S. officials say the strategy is on track, but many Syrians disagree. They say that, so far, the main beneficiary of the strikes aimed at Islamic State militants appears to be Syrian President Bashar al-Assad.
Militants have reportedly taken a third of embattled Kobane and seek to block escape routes.
“They want the U.S. to come in and take care of the problem,” a senior official said, but the Pentagon has said U.S. strikes alone can’t drive the Islamic State from Kobane, on Turkey’s border.
Kurdish officials said Islamic State fighters have pulled back from frontline positions in Kobane.
Stepped-up strikes in response to a Turkish appeal helped check the advance of Islamic State militants.