"Precipitously withdrawing USA forces from Afghanistan is a grave mistake".
In a February 2020 agreement with the administration of former president Donald Trump, the Taliban agreed to halt attacks and hold peace talks with the Afghan government, in exchange for a USA commitment to a complete withdrawal by May 2021.
The U.S. considers the re-emergence of al-Qaeda in the region after the draw-down of troops a "genuine threat" according to the official, who said the threat will be dealt with "directly" and by holding the Taliban accountable. "We believe we certainly can complete that by September, and the question of how long before September depends on conditions as the drawdown unfolds". "The Afghan government will struggle to hold the Taliban at bay if the coalition withdraws support", the assessment said.
The disclosure of the plan came on the same day that the United States intelligence community released a gloomy outlook for Afghanistan, forecasting "low" chances of a peace deal this year and warning that its government would struggle to hold the Taliban insurgency at bay if the US-led coalition withdraws support.
"There is no military solution to the problems plaguing Afghanistan, and we will focus our efforts on supporting the ongoing peace process", the senior administration official said.
Over the past year, USA military commanders and defence officials have said that attacks on U.S. troops have largely paused, but they say the Taliban have increased attacks on the Afghans.
USA officials provided details on Mr Biden's decision on condition of anonymity, speaking ahead of the announcement.
The official warned the Taliban - who are observing a truce with USA but not Afghan forces - not to strike coalition forces as they leave.
"Afghan forces continue to secure major cities and other government strongholds, but they remain tied down in defensive missions and have struggled to hold recaptured territory or reestablish a presence in areas abandoned in 2020", it said.
The Taliban, who enforce an austere brand of Sunni Islam, banned women from school, offices, music and most of daily life during their 1996-2001 rule over much of Afghanistan.
The Pentagon will provide more information at a later date about where the soon-departing troops will be going, the official added.
He said Mr Biden concluded any conditional withdrawal would be "a recipe for staying in Afghanistan forever".
India has said it would back a negotiated peace settlement via a regional process convened by the UN.
Afghan civilians, wary of the Taliban's return to power, have long paid a disproportionate price in the decades of bloody fighting and the rise of the Taliban has raised particular fears among many Afghan women.
The conference aims to speed up and give an worldwide dimension to slow-moving talks between the Taliban and Afghan government in Qatar.
In a sign of the wide global concerns, diplomats said that all of Afghanistan's neighbours would take part including Iran and China, which both have tense relations with the United States.
A senior Biden administration official said the pullout would begin before May 1 and could be complete well before the September 11 deadline.