Iran and Lebanon-based ally Hezbollah have extended their strong support to Syrian President Bashar al-Assad in the wake of the reported Israeli airstrike on the outskirts of Damascus.

"Hezbollah is ready to prevent Syria falling under the control of Tel Aviv and Washington. This is a strategy and not an intervention in the Syria crisis. It is an intervention in the conflict against America and Israel," said the chief of Hezbollah's political wing, Ibrahim Amin al-Sayed.

He also admitted that Hezbollah operatives have been active in the Syrian conflict.

"We are present in Syria at the political and the strategic levels and for the defence of the great cause [Palestine]. We have nothing to do with what the Syrian people want. On the contrary, we support the people in their demands to reach a situation that preserves their dignity and freedom and ensures their participation in political life," he said during a ceremony.

Earlier in the week, Hezbollah militant leader Sayyed Hassan Nasrallah conceded that insurgents have been involved in the fighting against Syrian rebels.

Nasrallah, who had a closed-door meeting with Russian Deputy Foreign Minister Mikhail Bogdanov, hinted at Russia and Iran militarily intervening in Syria to prevent toppling of Assad.

Assad belongs to the Alawite minority, an offshoot of Shiite Islam, strongly backed by the Shiite-dominated Iran and Hezbollah in the highly polarised region.

Meanwhile, Iran has strongly condemned the reported Israeli attack. Iran's army commander added that Iranian troops are ready to train the Syrian army.

"As a Muslim nation, we back Syria, and if there is need for training we will provide them with the training. The Syrian army has accumulated experience during years of conflict with the Zionist regime (Israel) and is able to defend itself and doesn't need foreign assistance," said General Ahmad Reza Pourdastan, according to Iran's Islamic Republic News Agency (IRNA).

Unconfirmed reports have also surfaced online that Assad is likely to declare an all-out war against Israel over the latest attack on its research facility near Damascus. However, it appears unlikely given the turmoil in Syria, opine experts.