Kurdish YPG fighters
Kurdish YPG fightersFlash 90

Masoud Barzani, president of the autonomous Kurdish Regional Government (KRG) in northern Iraq, issued a warning to jihadist groups in northern Syria, Saturday.

Calling on Kurdish parties in Iraq to launch an investigation into alleged massacres by Islamists against Syria's Kurdish population, Barzani warned that if such reports were found to be true, the KRG would intervene directly to defend their Kurdish brethren.

His calls are significant as they may signal an increased willingness by rival Kurdish groups to unite against Arab and Islamist terrorist groups in Syria.

His calls came only two days after the Iran-based Party of Free Life of Kurdistan (PJAK) announced that it is "ready to send fighters to Syrian Kurdistan to fight beside their people."

Not long afterwards, pictures were circulated online purporting to show PJAK fighters making their way to Syria.

Arab-Kurdish clashes

The Kurdish People's Protection Unit (YPG) has been involved in fierce fighting with Al Qaeda-linked Islamist groups such as Al Nusra and the Islamic State of Iraq and al-Sham (ISIS) over control of Kurdish-majority regions in northern Syria.

Not long after the start of the uprising against the Assad regime, government forces pulled out of Kurdish areas, and the YPG moved in to take control. Arab groups within the rebel Free Syrian Army (FSA) initially made a grab for Kurdish areas but were beaten back. In recent months, however, Al Nusra and ISIS have led a concerted and violent campaign to install their own independent "emirates," or Islamic mini-statelets in the region. That was met with fierce opposition by the YPG, who responded by ejecting Islamist forces from the border town of Ras al-Ain, near the Turkish border, among other areas.

Since then, anti-Kurdish rhetoric has reached fever pitch among Arab Islamists, with some mosques issuing fatwas (religious decrees) encouraging the wholesale slaughter of Kurds.

The Kurds are the largest indigenous Middle Eastern nation without a state. Their homeland, Kurdistan, is currently occupied by Turkey, Syria, Iran and Iraq, although Kurds in Iraq enjoy autonomy under the KRG, with their own police force and armed forces (known as peshmerga). Kurds in Syria make up around 10% of the population, and are concentrated largely in the north of the country.