Kabul: Taliban fighters could isolate Afghanistan's capital in 30 days and possibly take it over in 90, a US defence official cited US intelligence as saying, as the resurgent militants made more advances across the country.
The official, speaking to Reuters on condition of anonymity on Wednesday, said the new assessment of how long Kabul could stand was a result of the Taliban's rapid gains as US-led foreign forces leave.
"But this is not a foregone conclusion," the official added, saying that the Afghan security forces could reverse the momentum by putting up more resistance.
The Islamists now control 65% of Afghanistan and have taken or threaten to take 11 provincial capitals, a senior EU official said on Tuesday. Faizabad, in the northeastern province of Badakhshan, on Wednesday became the eighth provincial capital to be seized by the Taliban.
All gateways to Kabul, which lies in a valley surrounded by mountains, were choked with civilians entering the city and fleeing violence elsewhere, a Western security source there told Reuters. This made it hard to tell whether Taliban fighters were also getting through, the source said.
"The fear is of suicide bombers entering the diplomatic quarters to scare, attack and ensure everyone leaves at the earliest opportunity," he said.
Foreign countries are trying to ensure their staff leave Kabul quickly, five foreign security officials told Reuters. One said international airlines were also being asked to evacuate staff.
The loss of Faizabad was the latest setback for the Afghan government, which has struggled to stem the momentum of Taliban assaults.
President Ashraf Ghani flew to Mazar-i-Sharif to rally old warlords to the defence of the biggest city in the north as Taliban forces closed in.
We are closely watching the deteriorating security conditions in parts of the country, but no particular outcome, in our view, is inevitable.
Jawad Mujadidi, a provincial council member from Badakhshan, said the Taliban had laid siege to Faizabad before launching an offensive on Tuesday.
"With the fall of Faizabad, the whole of the northeast has come under Taliban control," Mujadidi told Reuters.
The Taliban want to defeat the U.S-backed government and reimpose strict Islamic law. The speed of their advance has shocked the government and its allies.
US President Joe Biden urged Afghan leaders to fight for their homeland, saying on Tuesday he did not regret his decision to withdraw. He said Washington had spent more than $1 trillion over 20 years and lost thousands of US troops.
The United States was providing significant air support, food, equipment and salaries to Afghan forces, he said.
White House press secretary Jen Psaki declined to comment on Wednesday about assessments that Kabul could soon be overtaken by the Taliban. "We are closely watching the deteriorating security conditions in parts of the country, but no particular outcome, in our view, is inevitable," she said.
The United States will complete the withdrawal of its forces this month in exchange for Taliban promises to prevent Afghanistan being used for international terrorism. Psaki said the timeline holds and reiterated the administration's view that Afghan forces have the US support they need to fight back.
The Afghans "need to determine ... if they have the political will to fight back and if they have the ability to unite as leaders to fight back," she said.
The Taliban promised not to attack foreign forces as they withdraw but did not agree to a ceasefire with the government. A Taliban commitment to talk peace with the government side has come to nothing.
A senior Taliban leader said the head of the group's political office, Mullah Abdul Ghani Baradar, met US Special Envoy for Afghan Reconciliation Ambassador Zalmay Khalilzad in Doha on Tuesday. No details of the meeting have been released.
The Troika Plus - a platform led by the United States, China and Russia - was expected to meet on Wednesday. The Taliban leader, requesting anonymity, said a Taliban delegation would take part.
The Taliban advances have raised fears of a return to power of the hardline militants who emerged in the early 1990s from the chaos of civil war. They controlled most of Afghanistan from 1996 to 2001, when they were ousted by a US-led campaign for harbouring al Qaeda chief Osama bin Laden.
A new generation of Afghans, who have come of age since 2001, fears the progress made in areas such as women's rights and media freedom will be squandered.
Afghan officials have appealed for pressure on Pakistan to stop Taliban reinforcements and supplies flowing over the border. Pakistan denies backing the Taliban.
During their previous rule, the Taliban never completely controlled the north. Now they seem intent on securing it before closing in Kabul.
Ghani is appealing for help from the regional warlords he spent years sidelining as he tried to project the authority of his central government over wayward provinces.
In the south, government forces battled Taliban fighters around the city of Kandahar and thousands of civilians from outlying areas had taken refuge there, a resident said. A doctor there said scores of bodies of Afghan forces have been received, and some wounded Taliban fighters have sought medical support.
The Taliban have captured districts bordering Tajikistan, Uzbekistan, Iran, Pakistan and China, heightening regional security concerns.