Kurdish forces have retaken a strategic hill overlooking the besieged city of Kobani from the Islamic State (Isis) in a symbolic blow to the terror group, according to a Kurdish spokesman.

Polat Can, the spokesman for the Kurdish People's Protection Units (YPG), who are defending the city, confirmed that Mistanour had been recaptured from IS, on his official Twitter account.

Idris Nassan, a local official in Kobani, also told Reuters by telephone that the YGP fighters had retaken the hill and the road which runs beside it.

"Isis was using this road for ammunition and fighters," he said, adding that the Kurdish fighters were targeting positions around Kobani such as Mistanour to prevent shelling of the city.

The hill is of strategic importance as it enables access to the predominantly Kurdish city, which is also known as Ayn al-Arab, and gives a view of all of the road links in the city. It also offered IS the range to fire mortars into the city from the hilltop.

Many Kurdish Twitter accounts supported Nassan's claims with Kurdish blogger Rodi Khalil tweeting that journalist Ibrahim Muslem witnessed YPG fighters on the hill.

Hundreds of Iraqi-Kurdish peshmerga forces arrived in Kobani last month to help the embattled Kurdish fighters to turn back the lightening advance of IS across northern and western Syria.

A US-led coalition has conducted a series of air strikes against the group in Syria, killing 865 people, including 50 civilians, since September, according to the Britain-based monitoring group the Syrian Observatory for Human Rights.

It also confirmed that at least 68 Islamist Nusra Front fighters were killed in the strikes.

The city - which sits on the Turkish border - remains under attack from IS despite weeks of the US-led coalition's air strikes.

Turkey has been hesitant to intervene because of suspicions that the Kurdish defenders of Kobani have close ties with the Kurdistan Workers' Party (PKK) which has waged a decades-long insurgency against Ankara.