Islamic State insurgents surrounded Kobani more than a month ago and are using weapons including tanks and armoured vehicles to attack Kurds.
US Central Command (CENTCOM) said it conducted four airstrikes, while three others were conducted by its partner nation forces.
Syrian President Bashar Assad is taking advantage of the US-led coalition’s war against the Islamic State group.
Islamic State group fighters seized at least one cache of weapons airdropped by US-led coalition forces.
The Pentagon said that US air strikes has helped to keep Islamic State militants from taking Kobani.
Kerry led the U.S. delegation to the inauguration of new Indonesian President Joko “Jokowi” Widodo.
The airdrops Sunday were the first of their kind and followed weeks of U.S. and coalition airstrikes in and near Kobani.
Six airstrikes took place near Kobani in Syria where reports indicate they successfully struck three IS buildings.
State Department spokesperson Jen Psaki, at the joint conference with Kirby, said the US is working with European leaders on de-legitimising the Islamic State.
“One of the reasons why you’re seeing more strikes there is because there is more ISIL there,” said Pentagon spokesperson.
Pins bearing the militants’ black-and-white flag are on sale at a jihad-themed bookstore near the Istanbul University campus.
IS poured in reinforcements and fired at least 11 rocket-propelled grenades into the town centre, said the Britain-based monitoring group.
The attacks come as Iraq faces its greatest challenge since the 2011 withdraw of U.S. troops and overture of militants.
A group that monitors the Syrian civil war said the Kurdish forces faced inevitable defeat in Kobani.
Despite Syrian Kurdish appeals for help, Turkey’s Foreign Minister played down the likelihood of its forces going to the aid of Kobani.