KABUL - A devastating earthquake in eastern Afghanistan, which killed at least 1,000 people and flattened homes in remote villages close to the Pakistani border, poses the biggest challenge yet for the Taliban since they seized power nearly a year ago.

The hardline Islamist group is governing an impoverished country beset by severe drought, widespread hunger and economic crisis and where the effects of decades of conflict are still keenly felt.

A regional offshoot of Islamic State has also claimed several major attacks, challenging Taliban promises to bring peace and stability to Afghanistan once it had defeated Western-backed troops and forced NATO soldiers to withdraw.

Now the earthquake risks exposing the limitations of an administration largely isolated from the outside world and desperately short of cash and resources.

While humanitarian assistance continues to flow, aid needed for longer-term development in Afghanistan was halted when the Taliban stormed Kabul last August.

Further angering the Taliban, billions of dollars in Afghan reserves also remain frozen overseas as the West pushes for concessions on human rights, particularly for girls and women.

"The sanctions imposed after the Taliban takeover ... and the economic collapse will make it incredibly difficult to respond with necessary medical and food aid, and to support reconstruction," said Ashley Jackson, co-director of the Centre on Armed Groups and an expert on the relationship between the Taliban and civilians.

So far, a handful of ageing helicopters have been flying to and from some of the worst-affected areas, carrying the injured out and ferrying in supplies of food and medicine.

The Taliban have appealed to the international community and several countries have promised humanitarian aid, some of which is already arriving. International aid agencies are also providing support on the ground.

Technical assistance, however, including specialist search and rescue teams that could fly in quickly from overseas, had yet to be deployed as of Thursday.

According to two UN officials and a Pakistani source speaking on Wednesday, teams from Turkey and Pakistan were on standby.

"The United Nations does not have search and rescue capabilities (themselves) in Afghanistan and Turkey is 'best positioned' to provide it," said deputy UN envoy in Afghanistan Ramiz Alakbarov, who coordinates humanitarian operations.

"We spoke about it with the embassy of Turkey here on the ground and they're waiting for the formal request."

Turkey and the Taliban have not responded to requests for comment on the issue. A Taliban news conference in Kabul scheduled for Thursday morning was cancelled.

It was not clear why requests were not made, although the UN humanitarian office (UNOCHA) said Taliban authorities had indicated late on Wednesday that search and rescue operations were 90% completed.

Two retired officers in Nepal involved in the aftermath of the 2015 quake that killed 9,000 people expressed surprise that the operation could be close to completion so soon, but one noted that if most damaged homes were small, it was possible.

ROADS HARD TO PASS

The area where the earthquake struck has seen little benefit from billions of dollars poured into Afghanistan by Western countries after the Taliban were toppled in 2001.

For the following 20 years, new roads were built and towns and cities grew, boosted by development aid despite a persistent insurgency by the Taliban and their militant allies that killed thousands of civilians and government soldiers.

Much of Paktika province, though, remained under the control of the Haqqani network, a feared jihadist group that now forms a key part of the Taliban government, and so was always considered high-risk territory.

The lack of investment has contributed to poor infrastructure in and around the epicentre of the earthquake, making access especially difficult.

Reuters reporters in the town of Gayan on Thursday said the local roads had no paving, meaning they were hard to negotiate as the rain fell.

The risk of landslides after the tremors was high and many buildings in the area were poorly constructed, consisting mainly of mud, leaving them more prone to collapse. Some villages are perched high on hillsides.

"We can't reach the area, the networks are too weak, we are trying to get updates," Mohammad Ismail Muawiyah, a spokesman for the top Taliban military commander in Paktika province, told Reuters, referring to telephone networks.

Jens Laerke, spokesman for UNOCHA, said on Wednesday the defence ministry had sent 45 ambulances to Paktika while the Paktika Provincial Health Department had dispatched eight ambulances and a team of doctors.

Heavy rain and wind had hampered efforts with helicopters reportedly unable to land, Laerke added.

Information from the scene on Thursday was patchy, but media have quoted locals describing how they helped the Taliban to search for survivors, digging bodies from the rubble, including those of children.

Aid groups said hospitals already stretched by malnutrition were now facing a huge influx of people injured in the earthquake.

In the wake of the disaster, some aid groups called for the international community to end Taliban isolation, arguing that humanitarian help was not enough to drag the country from crisis.

Some senior Taliban leaders are subject to sanctions on terrorism charges, complicating rehabilitation.

"The question is, will this disaster make the international community question the harmful costs that its policies are having on ordinary Afghans?" said Jackson.

Adnan Junaid, International Rescue Committee Vice President for Asia, added: "The international community must ... establish a roadmap that sets out strategies to resume development assistance, provide technical support to the central bank, and ultimately release Afghanistan's foreign exchange reserves."

(Additional reporting by Cecile Mantovani and Emma Farge in Geneva, Michelle Nichols at the United Nations, Mohammad Yunus Yawar in Kabul and Sayed Hassib in Gayan, Afghanistan; Writing by Mike Collett-White; Editing by Nick Macfie)