US President confirms leader dead as Taliban meet on his successor

US President Barack Obama confirmed on Monday that the leader of the Afghan Taliban had been killed in an American air strike, an attack likely to trigger another leadership tussle in a militant movement already riven by internal divisions.

Obama, on a three-day visit to Vietnam, reiterated support for the government in Kabul and the Afghan security forces, and called on the Taliban to join peace talks.

The president authorised the drone strike that killed Mullah Akhtar Mansour in a remote region just on the Pakistani side of the border with Afghanistan on Saturday, and Afghan authorities have said the mission was successful.

But U.S. officials held back from confirming that the Taliban leader had been killed in the attack until intelligence had been fully assessed.

"The Taliban should seize the opportunity to pursue the only real path for ending this long conflict - joining the Afghan government in a reconciliation process that leads to lasting peace and stability," he said.

However, he stressed that the operation against Mansour did not represent a shift in U.S. strategy in Afghanistan or a return to active engagement in fighting following the end of the international coalition's main combat mission in 2014.

The U.S. currently has 9,800 troops in Afghanistan, divided between a NATO-led mission to train and advise local forces and a separate counterterrorism mission fighting militant groups such as Islamic State and al Qaeda.

A decision is expected later this year on whether to stick with a timetable that would see the number of troops cut to 5,500 by the start of 2017.

CAN TALIBAN UNITE?

The Taliban has been pushing Afghan security forces hard since the launch of their spring offensive in April, but the attack is likely to disrupt the movement, at least temporarily.

Although some individual Taliban members have been quoted in media reports saying that Mansour was killed, the group's leadership, keenly aware of the need to limit damaging splits, has not issued its own confirmation.

"The leadership is being very careful because one wrong step could divide the group into many parties like former mujahideen," one Taliban official from the eastern province of Nangarhar said, referring to guerrilla leaders who fought the Soviets in the 1980s before splitting into warring factions.

A shura, or leadership council, has already begun meeting to choose a successor, a task that will be vital to protecting the unity of the movement.

Serious splits emerged last year when it was confirmed that Mullah Mohammad Omar, the group's founder, had been dead for two years, leaving his deputy Mansour in effective charge of the movement and open to accusations he had deceived his commanders.

One senior member of the shura, which is based in the western Pakistani city of Quetta, said that the choice for the next leader appeared to be shaping around Mansour's deputy, Sirajuddin Haqqani, or a member of the family of Mullah Omar, such as his son, Mullah Mohammad Yaqoob.

Haqqani, leader of an affiliated network blamed for a series of high-profile suicide attacks in Kabul, had the backing of Pakistan, while Yaqoob had support among members of the Afghan Taliban, the shura member said.

"We prefer someone from Omar's family to put an end to all internal problems," he said.