For free real time breaking news alerts sent straight to your inbox sign up to our breaking news emails Sign up to our free breaking news emails
The US is prepared to work together with Turkey on a military solution to “take out” Isis if political agreement proves impossible.
Vice president Joe Biden said a political deal would be better, but if that’s not possible the US would pursue other alternatives.
The US has been bombing Isis since June 2014 but has so far not committed ground forces for direct involvement in the conflict.
Mr Biden was speaking after meeting Turkish PM Ahmet Davutoglu in Istanbul.
"We do know it would better if we can reach a political solution but we are prepared ..., if that's not possible, to have a military solution to this operation in taking out Daesh," Biden said at a news conference after the meeting.
Dozens of US special forces already help rebels fighting Isis in Syria, although the troops are not intended for front line combat.
Show all 30 1 /30In pictures: Fighting between Kurds and Isis intensifies in Kobani In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani An explosion rocks Syrian city of Kobani during a reported suicide car bomb attack by the militants of Isis group on a People's Protection Unit (YPG) position in the city center of Kobani, as seen from the outskirts of Suruc, on the Turkey-Syria border
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani An explosion rocks the Syrian city of Kobani during a reported suicide car bomb attack by Isis
Getty
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani An explosion in the Syrian city of Kobani set off as fighting continues
Getty Images
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Heavy smoke rises following an air strike by the US-led coalition aircraft in Kobani
Getty Images
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani An unidentified armed man takes position near a building in the Syrian town of Kobani, as seen from near the Mursitpinar border crossing on the Turkish-Syrian border in the southeastern town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Kurdish fighters walk to their positions in Kobani
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Residents of Kobani walk in the streets of the besieged town, as seen from near the Mursitpinar border crossing on the Turkish-Syrian border in the southeastern town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani People's Protection Unit (YPG) fighters walk in the Syrian town of Kobani, as seen from near the Mursitpinar border crossing on the Turkish-Syrian border in the southeastern town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani People watch the Syrian town of Kobani from near the Mursitpinar border crossing, on the Turkish-Syrian border in the southeastern town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani A Turkish soldier stands on a top of a tank as he watches the Syrian town of Kobani from near the Mursitpinar border crossing, on the Turkish-Syrian border in the southeastern town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Smoke rises from the Syrian town of Kobani, seen from near the Mursitpinar border crossing on the Turkish-Syrian border in the southeastern town of Suruc. Kurdish forces defending Kobani urged a U.S.-led coalition to escalate air strikes on Isis fighters who tightened their grip on the Syrian town at the border with Turkey. A group that monitors the Syrian civil war said the Kurdish forces faced inevitable defeat in Kobani if Turkey did not open its border to let through arms, something Ankara has appeared reluctant to do
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Newly arrived People's Protection Unit (YPG) fighters walk in a line in the Syrian town of Kobani, seen from near the Mursitpinar border crossing on the Turkish-Syrian border
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Heavy smoke rises from the Syrian town of Kobani, seen from near the Mursitpinar border crossing on the Turkish-Syrian border in the southeastern town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Kurdish women mourn at the grave of a relative, who was a Kurdish fighter killed in fighting with the militants of the Islamic State group in Kobani, and was buried at a cemetery in Suruc
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Turkish army tanks mechanized units take position on top of a hill near Mursitpinar border crossing in the southeastern Turkish town of Suruc in Sanliurfa province
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Smoke rises after an US-led air strike in the Syrian town of Kobani. The air strikes pushed Isis fighters back to the edges of the Syrian Kurdish border town of Kobani, which they had appeared set to seize after a three-week assault, local officials said
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani A huge plume of smoke rises after an airstrike in eastern Kobani, Syria, behind a hilltop where militants with the Islamic State group had raised their flag on Monday
AP
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Turkish Kurds watch as airstrikes hit Kobani
AP
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Smoke rises from the Syrian town of Kobani as Turkish army tanks take position on the Turkish side of the border
Reuters
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Military aircraft flies over the Turkey-Syria border as it nears targets in Kobani
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Smoke rises after a US-led air strike in the Syrian town of Kobani
Reuters
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Turkish Kurds, on the Turkey-Syria border, watch over the border at the intensified fighting between Isis and Kurdish forces
AP
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Smoke rises during airstrikes on the Syrian town of Ain al-Arab, known as Kobani by the Kurds
Getty
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani A huge plume of smoke rises after an airstrike outside west Kobani, Syria
AP
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani A militant with the Isis group walks in the town of Kobani
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Militants with the Isis group, bottom, along with a machine gun-fitted pick up truck, partially seen bottom right, hold positions in Kobani, during intensified fighting with Syrian Kurds
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani People watch smoke rising from the Syrian town of Ain al-Arab, known as Kobani by the Kurds, after an air strike
Getty
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Smoke rises from a strike at an area of a mosque that destroyed its minaret, in Kobani during heavy fighting between militants with the Isis group and Syrian Kurds
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani Militants with Isis hold positions in Kobani, Syria, during intensified fighting with Syrian Kurds
AP
In pictures: Fighting between Kurds and Isis intensifies in Kobani Kobani A partial view of Kobani with a mosque's minaret
The latest round of Syria peace talks are planned to begin on Monday in Geneva, but were at risk of being delayed over disputes about who would form the opposition, Reuters reported.
A U.S. official later told Reuters that Biden was talking about a military solution to Islamic State, not Syria as a whole.
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies