There is a new push against the Islamic State of Iraq and the Levant (ISIL) group in Syria and Iraq.

And it seems to be a coordinated one, even though America's partners on the ground in both countries - the Kurds, are not allies.

In Syria, the Syrian Democratic Forces announced the start of an offensive that it hopes will end ISIL's presence in the northeastern corner of the country.

It will try to push ISIL from the southern countryside of the northeastern province of Hasakah.

Right across the border in Iraq, the Iraqi Kurdish force - the Peshmerga - along with thousands of Yazidi fighters, have been massing in the northwest for an offensive to retake Sinjar, which ISIL captured over a year ago.

Sinjar lies along a main highway linking ISIL strongholds: the Iraqi city of Mosul and the Syrian city of Raqqa. 

The land offensive on both sides of the border aims to interrupt ISIL supply lines, retake territory and put pressure on the group.

Losing Sinjar would make it more difficult for ISIL to resupply Mosul. And the assault in Hasakah will be a step towards isolating ISIL in Raqqa. 

Syria corner

"We announce the first step in our military campaign to liberate Syria from terrorists, many groups are participating in this effort with the coordination and support of the US-led coalition," the Syrian Democratic Forces said.

This newly formed alliance includes Kurdish, Arab and Assyrian forces. 

It is also expected to receive the help of US special forces which the Obama administration plans to deploy to Syria for the first time to help in the fight against ISIL.

US ground involvement in Syria is focused solely on fighting ISIL - Secretary of State John Kerry has said the US is not entering the war.

The Syrian Democratic Forces say their goal is not just to end ISIL's presence but build a democratic, unified and secular Syria - a goal shared by the US.

But the expected deployment and the support for the Kurdish People's Protection Units (YPG) is causing tension.


Related: New Syria Coalition launches offensive against ISIL


Other opposition groups are not just worried about the growing strength of the YPG but believe the priority should be to fight the Syrian government.

US backing for the Syrian Kurdish YPG force is not new. The so-called People's Protection Units have cleared many areas of ISIL with the help of coalition air strikes in recent months.

It has been trying to recruit more groups from Syria's Arab majority to create what Kurdish leaders say is a unified national force. Despite that, the YPG continues to be criticised by many including neighbouring Turkey for creating their own state - a charge it denies.

"They have been using Arab slogans and are trying to get Arab groups to join them [YPG] they are trying to achieve some credibility," Mario Abou Zeid, a Middle East analyst said.

"However it is clear from other rebels and factions in the opposition that this is merely a Kurdish force...The Kurds are the backbone and they are trying to implement a specific plan and have their own agenda in northern Syria."

The YPG already controls half of Turkey’s border with Syria all the way to Iraq where there have been tensions between Kurdish groups. 

Iraq corner

The fight for Sinjar has been repeatedly delayed because of internal rivalries among Kurdish groups. 

Sinjar is home to Iraq's minority Yazidi population. Some have joined the Peshmerga who are backed by Massoud Barzani's Kurdistan Democratic Party.

Others blame it for failing to rescue them when they were surrounded by ISIL. They have since joined the Kurdistan Workers Party (PKK) which helped evacuate them at the time. 

The KDP and the PKK have a tense relationship and have fought each other in the past. They now accuse the other of vying for power in this corner of Iraq.


Related: How evil is ISIL?


A KDP official was quoted as saying that the PKK along with the YPG have been informed not to intervene in the imminent Sinjar battle. 

It is not clear if the PKK and their ally, the Syrian Kurds will pull back from the permanent bases they have in the area. But what is clear is that America's partners on the ground in corners of Iraq and Syria are not friends. 

And there is a possibility of yet another future conflict. Sinjar is part of Iraq's so-called disputed territories - claimed by the Kurdistan regional government and the Baghdad central government.  

The fight against ISIL has brought to the surface existing differences and created new power struggles that won't go away after the battle against the armed group is won.