New Taliban leader Haibatullah Akhundzada called n the US Saturday to end its "occupation" of Afghanistan in his first message since being appointed the militant group's chief.

The message was released to mark the upcoming Muslim festival of Eid and comes two days after Taliban-claimed suicide blasts, targeting a convoy of buses transporting Afghan police cadets in Kabul, killed over 30 people and wounded more than 70.

"Admit the realities instead of useless use of force and muscle and put an end to the occupation," Akhundzada said in a speech on the eve of Eid-al-Fitr, the Muslim festival marking the end of the fasting month of Ramadan.

"Our message to the American invaders and her allies is this: the Afghan Muslim people neither fear... your force nor your stratagem. They consider martyrdom in confrontation with you as a cherished goal of their life," Akhundzada added.

He also called on neighbouring countries to join the fight against the US, saying the presence of Americans would "harm our mutual interest" and "destabilise the whole region".

"You are expected to join your voice with that of the Afghans to end the occupation or at least do not take steps which contribute to prolongation of presence of the Americans," he said.

The message is the first by Akhundzada since his predecessor Akhtar Mansour was killed during a US drone strike in neighbouring Pakistan in May.

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

Afghan officials have frequently accused Pakistan of harbouring and nurturing Taliban insurgents, who are waging an over-a-decade-long war against local and foreign troops in the country.

The Taliban have stepped up attacks after announcing Akhundzada as their new leader.

Observers say the once low-profile religious figure, who is seen as more of a spiritual figurehead than a military commander, will emulate Mansour in shunning peace talks and intensify attacks against the Afghan government. Analyst Ahmad Saeedi told AFP the statement was "softer" than that of his predecessors, but showed no indication the group wanted to join peace talks.

"I don't see anything new in the statement of the new Taliban leader Akhundzada. The new message does not have anything on peace talks and fate of war in the country. I think their policy is still the same," he said.

"He (the new leader) is once again insisting on fighting, calls it mandatory and challenging the US that they will not be victorious," he said.

Last month US President Barack Obama ordered the American military to tackle the resurgent Taliban more directly - in tandem with Afghan allies, ratcheting up a 15-year conflict he had vowed to end. Under the new rules, US troops can work more closely with local fighters in striking the Taliban.

They had previously been in an advisory role in Afghanistan since the start of 2015 and had only been authorised to hit Taliban targets for defensive reasons only, or to protect Afghan soldiers.

Thursday's twin suicide attack on a convoy of buses transporting newly graduated police came little over a week after 14 Nepali security guards heading to work at the Canadian embassy in Kabul were killed in a massive blast that left their minibus spattered with blood.