US-led coalition air strikes have managed to push back some fighters belonging to the Islamic State of Iraq and the Levant (ISIL) in the Syrian city of Kobane, but US and UK officials have said that air power alone cannot prevent the city from falling.
"Kobani could be taken. We recognise that," John Kirby, the press secretary for the US Defence Department told reporters on Wednesday.
"We're doing everything we can from the air to try to halt the momentum of ISIL against that town. Air power is not going to be alone enough to save that city."
Kirby's comments came as the coalition intensified its bombing of ISIL targets in Kobane, also known as Ayn al-Arab, while the Turkish military deployed tanks on its side of the frontier on Thursday.
In a statement on Wednesday, US Central Command (USCC) said it appeared that Syrian-Kurdish fighters continued to control most of the town and were holding out against ISIL.
But the Syrian Observatory of Human Rights (SOHR) said on Thursday that ISIL now controls more than a third of the town.
"All eastern areas, a small part of the northeast and an area in the south east [are controlled by ISIL]," the SOHR said.
If Kobani fell to ISIL, the armed group would be in control of more than half of Syria's 820km border with Turkey, but US Secretary of State John Kerry said the loss of the town would not be a strategic defeat.
Philip Hammond, the UK's foreign secretary, said that his country was a full partner of the coalition and was open to the possibility of extending its commitment to miliitary action within Syria, a move which he said would require parliamentary approval.
"We absolutely have not ruled out playing a role in Syria. We will require further parliamentary approval if we decide that that is the right thing for us to do," Hammond said.
Buffer zone confusion
Meanwhile, the US has been sending mixed signals over Turkey's proposal to create a buffer zone along the Syria-Turkey border, with Kerry initially saying that Washington was willing to consider the idea, but the White House later denied doing so.
US and Jordanian aircraft conducted eight additional strikes on ISIL around Kobane, for a total of 14 coalition strikes for the day and 19 bombing raids near the town since Tuesday, USCC, which is overseeing the airstrikes and US forces in the Middle East, said on Wednesday.
The latest strikes near Kobane destroyed five armed vehicles, an ISIL supply depot, a command centre, a logistics compound, and eight occupied barracks, the USCC said.
Another air raid southwest of the Syrian city of Raqqa destroyed four armed vehicles and damaged two more, it said.
US fighter jets and other aircraft also kept up bombing runs in Iraq, with one attack northwest of Ramadi, one in Mosul and another raid south of Kirkuk, it said.
About 200,000 people have already fled Kobane and surrounding villages since the fighting began.
Source: Al Jazeera and agencies