The pre-dawn attack came after the IS militants captured the defenders' headquarters on Friday, sparking fears they would cut off the last escape route to neighbouring Turkey.

Meanwhile, US officials warned that while attention is focused on Kobane, the jihadists have been piling on pressure in Iraq.

US military planes dropped ammunition, food and water Friday and Saturday to Iraqi troops under pressure from IS in north Iraq, the US Central Command said.

The move marked the first time that coalition aircraft airdropped supplies to Iraqi government forces. Similar drops were previously part of humanitarian missions for civilians, such as Yazidis and Turkmen.

Meanwhile British soldiers are in Iraq training the Kurdish peshmerga forces battling Islamic State jihadists, the Ministry of Defence in London said yesterday.

A "small, specialist team" is operating in Arbil, the capital of Iraq's autonomous Kurdistan region, training peshmerga how to use the heavy machine guns Britain supplied in September.

Military chiefs from the 21 countries already committed to the coalition are to meet in Washington this week to discuss strategy, Pentagon officials said.

US defence officials insist the primary focus of the campaign remains Iraq, where there are capable local forces on the ground to work with, particularly Kurds in the north.

Some of Anbar province fell to IS at the start of the year and most of the rest was seized by the Sunni extremists in a lightning sweep through Iraq's Sunni Arab heartland in June.

"I think it's fragile there now," one senior US defence official told AFP. "They are being resupplied and they're holding their own, but it's tough and challenging."

The renewed IS drive in Kobane sparked 90 minutes of heavy fighting before the jihadists fell back, the Britain-based Syrian Observatory for Human Rights said.

US-led coalition jets launched two air strikes against IS targets south and east of town early yesterday, said the group, which has a wide network of sources inside Syria.

The Observatory said a sandstorm later prevented more air raids, while fighting raged in southern Kobane and near the captured headquarters.

Small groups of Kurdish fighters were trying to harry the encircling jihadists with operations across the front line, Observatory director Rami Abdel Rahman told AFP.

UN envoy for Syria Staffan de Mistura warned Friday that 12,000 or so civilians still in or near Kobane, including about 700 mainly elderly people in the town centre, "will most likely be massacred" if the town falls.

Kobane was "literally surrounded" except for one narrow entry and exit point to the Turkish border, de Mistura said, urging Ankara to allow volunteers and equipment in to help defend the town.

Latest News from World News Desk