Afghan authorities scrambled Sunday to confirm the fate of Taliban leader Mullah Akhtar Mansour after US officials said he was likely killed in drone strikes -- a potential blow to the resurgent militant movement.

The Taliban have so far not commented on the very rare US attack deep inside Pakistan on Saturday, authorised by President Barack Obama.

The apparent elimination of Mansour, who had swiftly consolidated power following a bitter Taliban leadership struggle over the past year, could spark new succession battles within the fractious movement.

The attack took place in Pakistan's southwestern province of Balochistan bordering Afghanistan.

‘Mansour was the target and was likely killed’ in the remote town of Ahmad Wal by multiple unmanned aircraft operated by US special operations forces, an American official said Saturday.

Afghan President Ashraf Ghani's office on Sunday confirmed the strike, adding that they were investigating whether Mansour had in fact been killed.

The deaths of Taliban leaders have often been falsely reported, and Mansour himself was rumoured to have been killed last December.

‘The Afghan government is trying to gather details regarding the fate of Mullah Mansour,’ the presidential palace said in a statement.

‘This drone strike shows that terrorists fuelling conflict will not be safe anywhere.’

Two Pakistani intelligence officials told AFP the drones struck a Toyota Corolla near the city of Quetta, killing two people whose bodies were burned beyond recognition.

They did not confirm whether Mansour was among them but said the bodies had been moved to a hospital in Quetta.

Mansour was formally appointed head of the Taliban in July last year following the revelation that the group's founder Mullah Omar had been dead for two years.

The group saw a resurgence under the firebrand supremo with striking military victories, helping to cement his authority by burnishing his credentials as a commander.

The Taliban briefly captured the strategic northern city of Kunduz last September in their most spectacular victory in 14 years. The southern opium-rich province of Helmand is also almost entirely under insurgent control.

‘Mansour posed... an imminent threat to US personnel, Afghan civilians and Afghan security forces,’ US Secretary of State John Kerry told reporters during a visit to Myanmar Sunday.

‘He was also directly opposed to peace negotiations.’

- 'Fresh infighting' -

But Mansour's apparent death was not immediately seen as likely to push the Taliban closer to peace talks. It could press them to show they are still able to wage an aggressive battle, observers say.

‘The war has been going on for so long, the Taliban has so many leaders and so much ability to function at the local level even without strong central guidance, that we would be well advised to keep expectations in check,’ said Michael O'Hanlon of the Brookings Institution think-tank.

The drone attack came just days after representatives from the US, China, Pakistan and Afghanistan held another round of negotiations in Islamabad aimed at reviving long-stalled direct peace talks between the Afghan government and the Taliban.

However pressure has been building in recent months for the United States to return to direct attacks on the Taliban, particularly via air strikes.

‘We need to take the gloves off those forces already in-country,’ namely those belonging to the United States and NATO, and authorise air strikes, David Petraeus, the ex-CIA director and former commander of coalition forces in Afghanistan and Iraq, wrote in The Wall Street Journal in the past week.

NATO ended its combat mission in Afghanistan in December 2014, pulling out the bulk of its troops, although a 13,000-strong residual force remains for training and counterterrorism operations.

The Taliban, who announced the start of their annual spring offensive last month, have already stepped up their campaign against the Western-backed Kabul government for the season.

‘Mansour's apparent death will trigger fresh infighting and a new leadership succession battle inside the Taliban,’ Kabul-based analyst Mia Gul Waseeq told AFP.