| KASTAL, Syria
KASTAL, Syria After a week of clashes between anti-government rebels and Kurdish militants in Syria's Aleppo province, the two sides are observing a tenuous truce.
It is a war within a war which neither side wants.
"We want to fight the regime and instead we are fighting a new front that we don't need or have time for," said a fighter of the rebel Free Syria Army, warming himself over a fire on a on a mountain overlooking olive groves and stone villages.
"We should be in Aleppo fighting, instead we are camping."
The situation exemplifies the tangle of alliances, loyalties and rivalries - local and international - complicating the uprising against Syrian President Bashar al-Assad.
The FSA counts on the backing of Turkey, which gives it sanctuary over its border and is in the forefront of the diplomatic campaign against Assad.
The Syrian Kurdish militants are allied to the PKK (Kurdistan Workers Party), which is locked in a long struggle against the Turkish army to carve out an autonomous Kurdish region in southeast Turkey.
The Syrian Kurds have maintained their own unaligned militias and administer Kurdish areas in Aleppo province - scene of heavy fighting in the civil war. They are believed to be cutting deals with both the government and the opposition in order to maintain their autonomy.
The side conflict risks weakening the mostly-Arab rebels fighting Assad's better-armed forces.
Dozens of rebels and Kurdish fighters of the separatist Democratic Union Party (PYD) were killed in the past week in clashes that began in Aleppo city and have now spread to the countryside, just a few kilometers away from Turkey.
On the mountain dividing rebel-held areas from Kurdish towns to the northwest of Aleppo city, heavy clashes raged for days.
"We are not against all Kurdish groups, but these PKK-linked groups are helping the regime by attacking us, we had no choice but to act," says Mohammed Hamadeh, head of a rebel unit on the mountain.
"WE SHOULD BE ALLIES"
Despite some cooperation before the clashes, mistrust has always been high on both sides.
The rebels are wary of the PYD's neutral stance and believe it is working with Assad, while some Kurds are unhappy with the opposition's unwillingness to accept local Kurdish autonomy.
The PYD may have enjoyed a boost of popularity as locals watched Assad's forces pound rebel strongholds.
"I don't like the PYD, but they have taken care of the Kurds, unlike the rebels whose areas are totally destroyed. Now, many Kurds are taking a second look at the PYD," said Baran Afrini, a Kurdish opposition activist in the area who used to support the rebels.
In Kurdish districts of Aleppo, Syria's largest city, PYD fighters had been running a mini-state with daily services such as bread lines as well as security. Thousands of residents fleeing the daily bombing in most parts of the city took refuge in quiet Kurdish districts.
But when rebels last week moved into the Kurdish districts, Assad's forces responded by shelling the areas, provoking clashes.
Vital routes leading into the city are now at stake for both sides. Before the fighting, there was a silent agreement to allow each other passage on their roads. Both sides now want to ensure access to their strongholds.
"Our demand is for the Kurdish militants to move off of this mountain, and to guarantee us safe passage through their areas," Hamadeh said. "The Kurds have not yet responded."
Some Kurds say Assad's forces are trying to draw them to their side, despite their repression of Kurds before the uprising, just to sow divisions. The army withdrew from Kurdish areas without a fight, and many say it even gave weapons to the PYD as a way to antagonize the rebels and Turkey.
The internecine conflict between rebels and Kurds risks further drawing in Syria's neighbors. Growing Kurdish assertiveness could leave parts of northern Syria under the control of the Turkish PKK.
Basel, a 23-year-old fighter in jeans and carrying a Kalashnikov, is one of many Kurdish rebels now on the mountain fighting fellow Kurds.
Running through the trees, he shouts out a secret code to warn fighters that it is a rebel comrade coming up the mountain.
"I will fight for my country and my religion before I fight for my ethnicity," he said. "This is how the regime divides people. You have men who should be allies fighting among themselves."
(Editing by Dominic Evans and Angus MacSwan)