The Taliban seized more major cities as they raced towards full control of Afghanistan and inched closer to Kabul, with the United States preparing to airlift thousands of people a day out of the capital.

The first US Marines leading the evacuations landed at the civilian airport in Kabul, one of the few cities still in government hands after the Taliban took control of their spiritual heartland Kandahar, Afghanistan's second-largest city.

The scale and speed of the onslaught has shocked Afghans and the US-led alliance that poured billions into the country after toppling the Taliban in the wake of the September 11 attacks nearly 20 years ago.

Days before a final US withdrawal ordered by President Joe Biden, individual soldiers, units and even whole divisions have surrendered -- handing the insurgents even more vehicles and military hardware to fuel their lightning advance.

Pul-e-Alam, capital of Loghar province, was the latest city to fall Friday, putting the Taliban just 50 kilometres from Kabul.

Khairddin Logari, a resident of the capital, summed up the confusion. "We don't know what is going on," he told AFP.

British Defence Minister Ben Wallace said Friday that the hasty pullout, which London followed after Biden ordered the withdrawal of the larger US contingent, had been "a mistake".

Prime Minister Boris Johnson promised to "not turn our backs on Afghanistan" but acknowledged that outside powers had limited power to impose a solution.

- 'Completely conquered' -
Earlier Friday, officials and residents in Kandahar told AFP that government forces had withdrawn en masse to a military facility outside the southern city.

"Kandahar is completely conquered. The Mujahideen reached Martyrs' Square," a Taliban spokesman tweeted, referring to a city landmark.

Hours later, the Taliban said they had also taken control of Lashkar Gah, the capital of neighbouring Helmand province.

A security source confirmed the fall of the city, telling AFP that the Afghan military and government officials had evacuated Lashkar Gah after striking a local ceasefire deal with the militants.

In Herat on Friday, the Taliban captured the city's long-time strongman Ismail Khan, who helped lead the defence of the provincial capital along with his militia fighters.

The warlord's spokesman later confirmed Khan had been allowed to return to his residence following negotiations with the insurgents.

Helicopters flitted back and forth between Kabul's airport and the sprawling US diplomatic compound in the heavily fortified green zone -- 46 years after choppers evacuated Americans from Saigon, signalling the end of the Vietnam War.

Biden ordered troops to the airport to start pulling out some 30,000 embassy employees as well as Afghans and their families who fear retribution for working as interpreters or in other support roles for the United States.

Pentagon spokesman John Kirby said that most of the 3,000 troops would be in place by Sunday and "will be able to move thousands per day" out of Afghanistan. "Capacity is not going to be a problem," he told reporters.

He said Kabul was "not right now in an imminent threat environment" but that the Taliban appeared to be following a strategy of isolating the city to force a surrender. 

Britain is also evacuating citizens and other nations including Denmark, Norway and Germany announced that their Kabul embassies would be temporarily shuttered or operations reduced due to security concerns.

- Kandahar calm -
The insurgents have taken over more than half the nation's provincial capitals in the past week and encircled the biggest city in the north, the traditional anti-Taliban bastion of Mazar-i-Sharif, which is now one of the few holdouts remaining.

In Kandahar, resident Abdul Nafi told AFP the city was calm after the government forces pulled out early Friday.

"I came out this morning, I saw Taliban white flags in most squares of the city," he said. "I thought it might be the first day of Eid."

Pro-Taliban social media accounts have boasted of the vast spoils of war captured by the insurgents, posting photos of armoured vehicles, heavy weapons, and even a drone seized by their fighters at abandoned military bases.

UN Secretary-General Antonio Guterres renewed calls for a diplomatic solution and said he was "deeply disturbed" by accounts of poor treatment of women in areas seized by the Taliban, who imposed an ultra-austere brand of Islam on Afghanistan during their 1996-2001 rule.

"It is particularly horrifying and heartbreaking to see reports of the hard won rights of Afghan girls and women being ripped away," Guterres said.

Denmark, Norway shut Kabul embassies

Denmark and Norway will temporarily shut their Kabul embassies while Finland will evacuate up to 130 local Afghan workers, ministers from the Nordic countries said on Friday.

"The Danes in Afghanistan must leave the country immediately, the situation is very serious," Foreign Minister Jeppe Kofod told a news conference, adding that all embassy employees will be evacuated and the mission will be closed temporarily.

Norway echoed the move, with Foreign Minister Ine Eriksen Soreide telling a news conference that evacuation will also be available "to locally employed Afghans with immediate family in Norway who wish it".

Meanwhile Soreide's Finnish counterpart Pekka Haavisto said the country's parliament had agreed to "take in up to 130 Afghans who have worked in the service of Finland, the EU and Nato along with their families" because of "the quickly weakening security situation".

Haavisto said Finland's embassy would remain open for now, subject to ongoing security evaluations.

In line with its neighbour, Sweden's Foreign Minister Ann Linde tweeted on Friday that the country would only scale back its diplomatic presence for now, but that preparations for the evacuation of embassy staff were under way.

The announcements come as Washington announced on Thursday that it was sending thousands of troops to Kabul to evacuate diplomats and other nationals in the face of the Taliban's advance into the Afghan capital. 

The United Kingdom quickly followed the US lead. 

On Friday, Germany announced it was reducing its diplomatic staff in Kabul to the "absolute minimum" in the face of the Taliban offensive, which is approaching the Afghan capital.

US embassy asked to reduce sensitive material

The US embassy in Kabul on Friday ordered staff to get rid of sensitive material that could be used for Taliban propaganda as the insurgents rapidly advanced in Afghanistan.

In a memorandum to staff, a facility manager at the sprawling embassy directed employees to incinerators and other disposal sites for documents and equipment.

"Please also include items with embassy or agency logos, American flags or items which could be misused in propaganda efforts," the memo said.

A State Department spokesperson said that the embassy in Kabul was conducting a "drawdown."

"Drawdowns at our diplomatic posts around the world follow a standard operating procedure designed to minimize our footprint across various categories, including staffing, equipment and supplies," the spokesperson said.

The memorandum is the latest sign of mounting concerns for the safety of one of the largest US embassies in the world after President Joe Biden ordered a withdrawal of US troops after 20 years.

The Taliban on Thursday seized two other major cities, Herat and Kandahar, as they moved closer to the capital.

Biden on Thursday ordered 3,000 troops to the Kabul airport to move out US staff, with preparations underway to shift embassy operations to the airport as needed.

The Pentagon nonetheless said Friday it did not see an "imminent" threat to Kabul. The Biden administration is expected to take extraordinary precautions to guard US diplomats, mindful of the fierce backlash after an Islamist attack in 2012 on the consulate in Benghazi, Libya left dead four people including the ambassador.

Swiss offer visas to Afghan development agency staff

Switzerland said Friday it would repatriate three foreign ministry staff from Afghanistan and offer humanitarian visas to Afghan development agency workers and their families as the Taliban sweeps the country.

Switzerland has no embassy in Afghanistan, with diplomatic relations covered by the mission in neighbouring Pakistan.

However, the foreign ministry's international development arm, the Swiss Agency for Development and Cooperation (SDC), is present in Kabul.

Swiss ministers told a press conference that Bern would repatriate three Swiss SDC employees, the other three already being outside the country due to the worsening security situation.

Around 40 local workers with SDC, and their families, were being offered a humanitarian visa to come to Switzerland, taking the number to around 200 people in total.

"We are very concerned about the development of the situation in Afghanistan," Swiss junior foreign minister Livia Leu said.

She called for "an urgent dialogue on a political solution" and urged all parties to "respect international humanitarian law and human rights law".

Meanwhile the State Secretariat for Migration is suspending returns to Afghanistan until further notice.

Canada to take in 20,000 Afghan refugees 

Canada said Friday it will take in up to 20,000 Afghan refugees, including women leaders, government workers and others facing threats from the Taliban, as insurgents advanced across the country seizing major cities.

"The situation in Afghanistan is heartbreaking and Canada will not stand idly by," Immigration Minister Marco Mendicino told a news conference.

The refugees will include "particularly vulnerable" Afghans still in the country or who've already fled to neighboring states, which in addition to female leaders and government employees also comprises human rights defenders, persecuted minorities and journalists.

Several plane-loads of asylum seekers have already departed with the first one landing Friday in Toronto, Mendicino said.

As the Taliban advances on the capital Kabul, officials said Canadian special forces form part of a contingency plans to airlift Canadian embassy staff, but details were not provided due to the sensitive nature of the security operation.

Earlier Friday, many countries including Spain, Denmark, Norway and the Netherlands announced the withdrawal of staff from their respective embassies.

Canada has said it is monitoring the situation in Afghanistan "very closely" and working with its allies on the ground.

"Protecting the Canadian Embassy and our staff is our top priority," said Foreign Minister Marc Garneau.

On Twitter, he said that Canada "owes Afghans a debt of gratitude and we will continue our efforts to bring them to safety." 

Spain starts repatriating personnel, citizens from Kabul embassy

Spain announced Friday it had begun to repatriate its few citizens left in Afghanistan as well as personnel from its embassy in Kabul and Afghan colleagues amid the Taliban's lightning advance across the country.

Foreign Minister Jose Manuel Albares signalled "the start of repatriation of embassy personnel, Spaniards who remained in the country as well as Afghans and their families who worked at our side," according to a statement.

"Spain is ready for any eventuality, including that of emptying the embassy if necessary," the foreign minister said.

Apart from those in the embassy, there remained six Spanish citizens in Afghanistan on Friday, the ministry said.

The ministry is working with other ministries "to coordinate the transfer of Afghan citizens who collaborated in military missions and Spanish cooperation projects in Afghanistan," the statement said.

Since 2014, Spain has granted refugee status to 55 Afghan translators and their relatives, according to the interior ministry.

The interior ministry will "process" any application for international protection made by Afghan translators and others who worked for Spanish forces after they arrive in Spain, an interior ministry source told AFP.

A defence ministry source told AFP that Madrid "is working on the possibility of bringing the translators and other people who worked with Spanish forces" in Afghanistan to Spain, but did not specify a timeline.

Spain pulled its last troops out of Afghanistan in May 2021 after a mission which lasted nearly two decades in which about 100 Spanish soldiers lost their lives.

The United States and other countries like the United Kingdom, Norway, and Denmark have announced plans to evacuate embassy personnel and citizens from Afghanistan.