Beirut: Al Qaeda`s Syrian offshoot on Wednesday made an oath of loyalty to the Islamic State of Iraq and the Levant at a key town on the Iraqi border, a monitor said.
The Syrian Observatory for Human Rights said the merger is significant because it opens the way for ISIL to take control of both sides of the border at Albu Kamal in Syria and Al-Qaim in Iraq, where the jihadist group has led a major offensive this month.
After months of fighting ISIL, al Qaeda`s official Syrian arm the Al-Nusra Front "pledged loyalty to ISIL" in Albu Kamal, said Observatory director Rami Abdel Rahman.
"The pledge comes amid advances by ISIL in Deir Ezzor province" in eastern Syria on the Iraqi border, Abdel Rahman told AFP.
Although both ISIL and the Al-Nusra Front are rooted in al Qaeda, the two have been rivals for much of the time that ISIL has been involved in Syria`s civil war since spring last year.
"They are rivals, but both groups are jihadist and extremists. This move will create tension now with other rebel groups, including Islamists, in the area," said Abdel Rahman.
Meanwhile, the Syrian air force carried out air raids targeting ISIL-controlled Raqa in the north of the country and Muhassen in the east.
President Bashar al-Assad`s regime has rarely targeted ISIL bastions, except in recent days after the group and other Sunni militants launched an offensive in Iraq, wresting control of Mosul and other pars of Iraq.
ISIL aspires to create an Islamic state that straddles Iraq and Syria.