Lots of officers from Free Syrian Army (FSA) have joined Islamic State militants, one FSA commanders told RT. That's despite the rebels' centers repeatedly getting attacked by the extremists.

“But lots of our officers joined Islamic State because of ideology,” Hussam Alawak, a commander of the Free Syrian army, told RT. He added that some extremists from the Islamic State's (IS, formerly known as ISIS/ISIL) branch in Iraq come to FSA centers and “cause trouble for them.”

“They [IS] took lots of people from our army to achieve their goals of expansion, to control oil regions in Syria. They attacked us with very dense fire in the Al-Bab region [Aleppo province, northern Syria], so we had to tactically retreat to other places."

READ MORE: FSA proposes Russia to hold talks on Syrian crisis in Cairo – official

According to the Alawak, FSA also hopes that Russians and Syrians “can work hand-in-hand when it comes to counter terrorism and extremism in the region.”

“We hope the Russian role in the Syrian crisis will be effective and Russia will be on the side of justice, dealing with all parties in the Syrian crisis,” he added.

URGENT: Russia is ready to offer aerial support to Syrian opposition fighting ISIS - Lavrov https://t.co/KQAdAUFJ2Epic.twitter.com/I2IIREIQvx — RT (@RT_com) October 24, 2015

Russia has repeatedly said it never stopped working “either with Syrian President Bashar Assad, or with the Syrian opposition, including the Free Syrian Army.”

Russian Foreign Minister Sergey Lavrov earlier announced that Moscow is ready to provide air support, in the form of airstrikes, to help Syrian opposition forces, like the Free Syrian Army, which is fighting IS militants.

“We are ready to back the patriotic opposition, including the so-called Free Syrian Army, with our air support,” Lavrov said.

FSA forces, in turn, said on Sunday that they have sent Russia a proposal to hold talks on the Syrian crisis in Cairo, Egypt, adding that the opposition is ready for dialogue with Moscow.

“The Free Syrian Army is ready for dialogue with Russia. We need to organize a new meeting, so that we can present our position and discuss our collective actions,” one of the founders of FSA and the coordinator of National Salvation Front Fahad Al-Masri told RIA Novosti. The group, however, hasn’t yet received an answer from Moscow.

The military operation targeting positions of Islamic State militants in Syria was launched by Moscow September 30 following a formal request from Assad. In the past three days the Russian aviation group in Syria has hit 258 targets belonging to IS and Al-Nusra Front terror groups, the Defense Ministry said.

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