0413 GMT June 26, 2022
The House of Commons Foreign Affairs Committee probe revealed a "fundamental lack of planning, grip or leadership at a time of national emergency" before and during the Taliban takeover of Kabul in August 2021, according to AFP.
"The manner of our withdrawal from Afghanistan was a disaster and a betrayal of our allies that will damage the UK's interests for years to come," the report said.
Already in August, the government faced a torrent of criticism over its hurried withdrawal following the decision of its ally, the United States, to end its 20-year presence.
Hundreds of Afghans eligible for relocation were left behind, many with their lives potentially at risk after details of staff and job applicants were left at the abandoned British Embassy compound in Kabul.
At the time, Prime Minister Boris Johnson hailed a mission "unlike anything we have seen in our lifetimes" with the UK airlifting over 15,000 people in two weeks.
Then-foreign secretary Dominic Raab was heavily criticized for not immediately leaving a beach holiday when the Taliban took control.
Committee MPs spoke with UK officials as well as Afghans who were evacuated, and received evidence from a "wide range of stakeholders".
During the run-up to the Taliban takeover, the government and civil servants suffered from an "optimism bias" that the US would change its mind about withdrawing, despite it having been announced by former president Donald Trump in February 2020, said the report.
"The UK government failed adequately to shape or respond to Washington's decision to withdraw, to predict the speed of the Taliban's takeover, or to plan and prepare for the evacuation of our Afghan partners," it added.
"Most damning for the Foreign Office is the total absence of a plan for evacuating Afghans who supported the UK mission, without being directly employed by the UK government, despite knowing 18 months before the collapse of Afghanistan that an evacuation might be necessary."