Turkey sets the tone when it spells out its conditions to help fight Daash

The country's Prime Minister, Ahmet Davutoglu, said that any military operation to free Kobane must involve arming regular Syrian rebel groups rather than the Kurdish militants who have so far defended the town. Turkey has refused to help the Kurdish fighters so far, claiming that many of them belong to the militant Kurdistan Workers' Party (PKK), which has waged a separatist insurgency against the Turkish state.

"Equip and train the Free Syrian Army so that if the Islamic State leaves, PKK terrorists should not come," Davutoglu said, aiming his comments at the US.

Davutoglu's remarks, made in an interview with the BBC, follow mounting international criticism of Turkey for refusing to intervene in the siege of Kobane, where a small force of lightly-armed Kurdish fighters have spent the last month holding out against heavily-armed Islamic State militants. US air strikes have slowed the Islamic State's advance, but failed to significantly loosen their grip, fuelling calls for Turkey to join the fray. So far, forces from the Turkish army - the second largest in Nato - have simply observed the siege of Kobane from just across the border.

On Tuesday, Davutoglu said that Turkish troops would only be sent into battle if the West committed ground forces into Syria as well, a prospect that Washington and Britain have already ruled out.

"If they don't want to send their ground troops, how can they expect Turkey to send Turkish ground troops with the same risks on our border," he told the BBC.

He hinted, though, that Turkish air bases might be used for US-led airstrikes if American jets targeted the forces of the Syria's President Bashar al-Assad as well hitting Islamic State fighters. The US has already asked to use Turkey's air base at Incirlik for the strikes, which would be easier than carrying them out from aircraft carriers in the Persian Gulf, but Turkey has so far refused.

Davutoglu, a noted opponent of Mr Assad, said: "We will help any forces, any coalition, through air bases (within Turkey) or through other means if we have a common understanding to have a new pluralistic, democratic Syria."

As Davutoglu spoke, a column of peshmerga fighters from Iraqi Kurdistan began their journey towards Kobane, where they will act as back-up forces. Bowing to Western pressure, Ankara has reluctantly agreed to let the peshmerga forces go through after receiving assurances that they would seek only to fend off the Islamic State rather than seek any future cause with the PKK.

The 40-vehicle column, carrying 80 fighters and armed with machineguns and artillery, was expected to cross into Turkey last night, Kurdish officials told the AFP news agency. A further 72 fighters were due to fly into Turkey early on Wednesday, also bound for Kobane, where yesterday palls of smoke rose over the town as Islamic State fighters set fire to tyres in a bid to prevent air strikes.

Turkey and the West have become progressively more at loggerheads over how end the Syrian crisis, despite both sides being keen to see the back of President Assad. One of the most powerful countries in the Middle East, Turkey was quick to call for President Assad's overthrow, a move initially hailed by the West as a welcome lead from an Islamic country. But Ankara has since been accused of helping more radical rebel groups to cross the borders into Syria, paving the way for the creation of extremist outfits like the Islamic State.

Davutoglu continued to paint a disdainful picture of Western nations either dithering or lacking the military appetite for a long-term solution to the Syrian crisis. Turkey, he said, "did not want to be part of the game for a few weeks or months just to satisfy American or European public opinion".

He also repeated his call for an internationally-backed no-fly zone over northern Syria, from where moderate rebel groups could operate free from President Assad's jets. America has ruled out such a no-fly zone on the basis that enforcing it would force US jets to directly challenge President Assad's air defence system.