A senior commander of the global militant Islamist organisation al-Qaeda has been killed in a clash with Syrian government forces.

According to The Sunday Express report, the al-Nusra Front, al-Qaeda's Sunni Islamic jihadist militia fighting against forces deployed by Syrian President Bashar Hafez al-Assad's government, that confirmed the death of its leader, Sheikh Abu Sulaiman Al Masri.

A graphic photo circulating online shows the al-Qaeda leader's body, with blood gushing down his forehead. He was believed to have been fatally shot in the Syrian capital of Aleppo.

Al-Masri, whose real name is believed to be Mahmud Maghwari, is an Egyptian national, a religious leader and an experienced jihadi previously sentenced to death in his homeland for fighting with Hamas in Gaza before he joined al-Nusra.

The al-Qaeda leader reportedly had to amputate one of his thumbs and a few fingers after injuring them in battle.

Rami Abdurrahman, head of the UK-based Syrian Observatory for Human Rights (SOHR), said in a Bloomberg report that al-Masri's death was a devastating blow on al-Qaeda's operations in Syria.

The morale of al-Nusra fighters in Syria battling Assad's forces is expected to plummet following the killing of their leader, Abdurrahman said.

Al-Masri's demise came at a time when Syrian government forces are being reinforced by Russian troops to carry out airstrikes targeting the Islamic State jihadist organisation.

Russian and Syrian government forces seek to wipe out the group and restore a crucial supply line to a government-held part of Aleppo.

The campaign has so far taken the lives of 28 ISIS militants and 21 troops and militia, according to SOHR data cited by The Daily Mail.

Just last Friday, the jihadists managed to take and isolate the highway from the rest of government territory in Aleppo's west.