LONDON: Nearly two years after the killing of Osama bin Laden, the death in Mali of Algerian commander Mokhtar Belmokhtar, if confirmed, would be a serious blow to al Qaeda's efforts to recover its cohesion as a force for global jihad.

Official sources question how far al Qaeda's leadership is able to influence its branches in far-flung North Africa, arguing that an intensive U.S. drone campaign on its presumed haven in Pakistan's tribal areas bordering Afghanistan has severely damaged its ability to exercise command and control.

But Belmokhtar - whom Chad said its forces had killed in northern Mali on Saturday - nonetheless represented an important link to the jihadi organisation's roots, having trained in Afghanistan in the early 1990s, where according to two former mujahideen commanders he was close to al Qaeda.

The presumed mastermind behind a hostage-taking at an Algerian gas plant in January, he had also staked a claim to represent core al Qaeda causes when the hostage-takers demanded the release from U.S. prisons of Egyptian Sheikh Omar Abdel-Rahman and Pakistani neuroscientist Aafia Siddiqui.

Abdel-Rahman, the blind cleric jailed for involvement in the 1993 bombing of the World Trade Center, and Siddiqui, whose uncle by marriage was Sept 11 mastermind Khaled Sheikh Mohammad, are highly sensitive cases in Egypt and Pakistan, used to win support for al Qaeda's cause and draw in recruits and funding.

"If confirmed, his death would definitely be a blow for the jihadi networks in North Africa and the Sahel," said Camille Tawil, a journalist at al Hayat newspaper and a leading authority on North African jihadism. "He is for sure one of the oldest recognisable figures in the region with a wide and strong network of cells made up of locals as well as foreigners."

A jihadist quoted by the SITE monitoring service rejected reports that Belmoktar had been killed, saying he was alive and would soon release a message. There has been no confirmation of his death outside of Chad.

Chad's President Idriss Deby said on Friday his soldiers had also killed al Qaeda commander Abdelhamid Abou Zeid in an operation in the same area - Mali's Adrar des Ifoghas mountains near the Algerian border.

An Algerian security source said it was "very likely" Belmokhtar had been killed. Others were more sceptical, noting his experience and knowledge of the desert terrain could have helped him escape after French-led military operations were launched against the Islamist militants in Mali this year.

The killing of the two commanders, if confirmed, would also not be death blow for al Qaeda in the Islamic Maghreb (AQIM). Before being driven out of towns in northern Mali, the militants had dug deep roots among the local population and won many new recruits who are expected to continue the fight.

Belmokhtar's death - far more so than that of Abu Zeid - would nonetheless break a chain linking those dedicated to al Qaeda's ideology from Mauritania in the west, eastwards through Mali to Libya, Egypt, Somalia, Nigeria, Yemen and Pakistan.

It would also come at a time when bin Laden's successor, the Egyptian Ayman al Zawahiri, has to prove his credentials to keep the different parts of al Qaeda together.

Zawahiri has neither the iconic stature nor the background as a former Saudi national that allowed bin Laden to act as a unifying force before he was killed by U.S. forces in the Pakistani town of Abbottabad in May 2011.

"One of the major challenges which Zawahiri will have to face is to reassure members of al Qaeda that as its leader, he will not follow an Egypt-centric strategy" said Arslan Chikhaoui, a security analyst and chairman of a consultancy firm based in Algiers.

"He will have to work particularly hard to keep al Qaeda in the Arab Peninsula (AQAP) and al Qaeda in the Islamic Maghreb (AQIM) on the side of the al Qaeda network and convince them of their interest in being inside the organisation and not on the outside," he said in a report released last month.

And while support for al Qaeda's ideology will be carried forward by younger recruits, Belmokhtar was, or is, the last in the Sahel connected to the early days of global jihad.

According to two former mujahideen commanders who knew him, he was 19 years old when he reached Afghanistan in 1991. He spent 1-1/2 years there, losing an eye during a bomb-making class, before returning to Algeria to join its bloody civil war.

A statement on his reported death, released by U.S. Representative Ed Royce, chairman of the House Foreign Affairs Committee, described him as "one of the most elusive and deadly terrorists in North Africa". Underscoring his importance, the statement added that, "Belmokhtar has been tracked by the Central Intelligence Agency since the early 1990s."

Belmokhtar, along with many other Algerian Islamists who fought in the civil war, officially joined al Qaeda when his group became al Qaeda in the Islamic Maghreb in 2007.

Before the attack on the Algerian gas plant at In Amenas, in which more than 60 people were killed, some experts had suggested Belmokhtar had drifted away from jihad in favour of kidnapping and smuggling weapons and cigarettes in the Sahara, where he earned the nickname "Mr. Marlboro".

Yet in a video released last year he had publicly pledged his loyalty to Zawahiri and Afghan Taliban leader Mullah Muhammad Omar. Rather than drifting away from jihad, he appeared to be combining it with smuggling and kidnapping to raise funds.

Underscoring his geographical reach, he had support in Mauritania, an old base of operations for him. He had also been reported to have bought weapons from jihadis in Libya - part of the huge cache which also found its way into the hands of Islamist militants in the Sinai in Egypt after the overthrow in 2011 of Libyan dictator Muammar al Gaddafi.

Little is known of how Zawahiri plans to leverage the fragmented parts of the al Qaeda franchise to retain its global cohesion and relevance after the "Arab spring" uprisings led to the overthrow of dictators it had opposed.

But Algerian analyst Chikhaoui argued that Zawahiri had named among his closest circle in the central leadership men from North Africa with ties to AQIM in order to focus initially on Libya, Algeria and the Sahel.

"Zawahiri sees Libya in particular as a potential rear base for Egypt, considered the key to the Arab world," he wrote. Having ensured that AQIM remained within the ambit of the core organisation, he would seek to keep AQAP on board.

Belmokhtar's death, if confirmed, would remove a key player in that scenario - a man who with the attack at In Amenas burnished his jihadi credentials and proved al Qaeda remained a potent threat to Western interests.