SITUATION REMAINS "FRAGILE"
In a brief statement, the US Central Command said US Air Force C-130 aircraft "delivered weapons, ammunition and medical supplies that were provided by Kurdish authorities in Iraq and intended to enable continued resistance against ISIL's attempts to overtake Kobani," using an acronym to refer to Islamic State.
The Central Command said 135 US air strikes near Kobani in recent days, combined with continued resistance against Islamic State on the ground, had slowed the group's advances into the town and killed hundreds of its fighters.
"However, the security situation in Kobani remains fragile as ISIL continues to threaten the city and Kurdish forces continue to resist," the statement said.
"We understand the longstanding Turkish concern with the range of groups, including Kurdish groups, that they have been engaged in conflict with," he added. "However, our very strong belief is that both the United States and Turkey face a common enemy in ISIL and that we need to act on an urgent basis."
The Turkish presidency said Obama and Erdogan had discussed Syria, including measures that could be taken to stop Islamic State's advances, and Kobani.
In a statement published on Sunday, it also said Turkish assistance to over 1.5 million Syrians, including around 180,000 from Kobani, was noted in the conversation.
In comments published by Turkish media on Monday, Erdogan equated the main Syrian Kurdish political group, the PYD, with the PKK, describing both as terrorist organisations.
"It will be very wrong for America with whom we are allied and who we are together with in NATO to expect us to say 'yes' (to supporting the PYD) after openly announcing such support for a terrorist organisation," Erdogan said.
Kobani is one of three areas near the border with Turkey where Syrian Kurds have established their own government since the country descended into civil war in 2011.