“The Al-Nusra Front is simply a branch of the Islamic State of Iraq,” ISI’s chief Abu Bakr al-Baghdadi said in recording posted online, adding the group was fighting for an Islamic state in Syria, AFP reported.
The groups would be combined and called the Islamic State in Iraq and the Levant, Baghdadi said, describing Al-Nusra front leader Abu Mohammed al-Jawlani as “one of our soldiers”.
“We chose al-Jawlani… as well as other fighters to go from Iraq to Syria… We prepared plans and work policies. We gave them money and personnel support,” said Baghdadi.
His declaration came a day after an Al-Nusra-style suicide car bomb attack in the heart of the Syrian capital Damascus killed at least 15 people and wounded 146 others.
It also came after Al-Qaeda’s global chief, Ayman al-Zawahiri, urged rebels to fight to establish an Islamic state in Syria, in an audio message posted on the Internet on Sunday.
Al-Nusra Front, which announced its creation in a January 2012 video, is a magnet for foreign fighters seeking to take part in the insurgency against the Syrian government.
The New York Times reported last month the CIA was helping Arab states and Turkey to boost arms shipments to Syria’s rebels.
Asked on Tuesday if the United States was stepping up its military options in Syria, U.S. Secretary of State John Kerry said such moves would be “part of our discussions this week in Washington”.
Kerry also said he would meet with the Syrian opposition in London, in remarks to journalists shortly before he departed Israel for the British capital.
“We will be discussing various means about having an impact on President Assad’s calculations about where the battlefield is going,” said the top U.S. diplomat.
“We are left with no choice but to try find ways to get him to think differently about what lies in the future.”
In March, France and Britain argued that scrapping an EU arms embargo for Syria would tilt the balance on the ground and help prompt a political settlement of the conflict.
No group claimed responsibility for Monday’s bombing in Damascus.
Meanwhile, the United Nations said that aid operations for Syrian refugees have reached breaking point in the face of a massive funding shortfall, amid fears the number of people fleeing the conflict could triple.
The Syria crisis began in March 2011, and many people, including large numbers of soldiers and security personnel, have been killed in the violence.
Several international human rights organizations have accused foreign-sponsored militants of committing war crimes in Syria.
In an interview recently broadcast on Turkish television, President Assad said that if the militants fighting against the Syrian government take power in his country they could destabilize the entire Middle East for decades.
“If the unrest in Syria leads to the partitioning of the country, or if the terrorist forces take control… the situation will inevitably spill over into neighboring countries and create a domino effect throughout the Middle East and beyond,” he added.
The Syrian government has called on the armed foreign-sponsored militants to lay down their weapons or face the consequences.
The government made the demand on Sunday in a in a text message sent to people across the Arab country, Xinhua news agency reported.
It said that “to all those carrying weapons against the state, be rational and quick to lay down weapons because the men of the Syrian army are coming.”
“Our duty is to protect the homeland, and confronting terrorism is a national and legitimate duty,” the message said.
The warning came as the Syrian forces continue mop-up operations against the foreign-backed militants across the country.
Syria has been experiencing unrest since March 2011. Many people, including large numbers of Army and security personnel, have been killed in the violence.
The Syrian government has said that the chaos is being orchestrated from outside the country, and that a very large number of the militants operating in the country are foreign nationals.
Several international human rights organizations have accused foreign-sponsored militants of committing war crimes.
In an interview recently broadcast on Turkish television, Syrian President Bashar al-Assad said that “Turkey’s government officially harbors terrorists and sends them into Syria. They’re also crossing over from Jordan.”