The former president of Afghanistan, Burhanuddin Rabbani, was killed in a suicide bomb attack on Tuesday afternoon. He was considered vital to peace efforts efforts to bring Taliban leaders into the reconciliation process.

Rabbani was killed in the explosion outside his Kabul residence. Masoom Stanekzai, another pivotal figure in Hamid Karzai's reconciliation strategy, was seriously injured.

Ministry of Interior sources told The Daily Telegraph the attack had been carried out by two suicide bombers at Rabbani’s home in the upmarket Wazir Akhbar Khan area, near the American Embassy.

Rabbani was a former Mujahideen leader, who became president after the Soviets left Afghanistan in 1992. He was president until he was ousted by the Taliban in 1996. Subsequently he became the nominal head of the Northern Alliance, who opposed the rule of the Taliban.

Nato secretary general condemned the killing, which he said was "an attack on the Afghan people" as they prepared to to take over responsibility for their own security.

"On behalf of the Nato Alliance, I send my heartfelt condolences to the families and friends of those brave Afghans who died and were injured today in the pursuit of peace and reconciliation," he said.

"I pay special tribute to Dr Rabbani, whom I met earlier this year in Kabul, and who was leading the peace and reconciliation effort that is vital for the future of Afghanistan."