An independent public inquiry into the government’s handling of the coronavirus pandemic will begin in the spring of next year, the prime minister has announced.
More than 127,000 people have died within 28 days of a positive coronavirus test since the pandemic began last year, while more than 150,000 deaths have mentioned COVID-19 on the death certificate.
The PM said that "amid such tragedy the state has an obligation to examine its actions as rigorously and as candidly as possible" and "learn every lesson for the future".
Given the potential threat of new COVID variants and the possibility of a winter surge, Mr Johnson said he expected the "right moment" for the inquiry to begin is spring 2022.
"This inquiry must be able to look at the events of the last year in the cold light of day and identify the key issues that will make a difference for the future," he said.
"Free to scrutinise every document to hear from all the key players and analyse and learn from the breadth of our response.
"That’s the right way, I think, to get the answers that the people of this country deserve and to ensure that our United Kingdom is better prepared for any future pandemic."
The PM said his government would work closely with the devolved administrations in Scotland, Wales and Northern Ireland before setting out the inquiry’s terms of reference.
He did not reveal when the inquiry would be expected to produce its final report, saying only: "I think we owe it to the country to have as much transparency as we possibly can and we owe it to the country to produce answers in a reasonable timescale."
Jo Goodman, co-founder of the COVID-19 Bereaved Families for Justice group, said the announcement was a "huge relief" but spring 2022 is "simply too late to begin".
Downing Street declined to say whether it will report back before the next general election, which is due in 2024.
"The timescale is down to the chairman, that is something that we will want to agree with the chairperson when they are appointed," the PM’s spokesman said.
Number 10 said Mr Johnson would be willing to give evidence under oath if asked.
Mr Johnson also announced in the Commons that a commission on COVID commemoration would be set up.
Labour leader Sir Keir Starmer welcomed the inquiry, but questioned why it could not be launched sooner.
He urged the PM to consult with the families who have lost loved ones to COVID.
"This inquiry will only work if it has the support and confidence of the families," Sir Keir said, adding that frontline workers should also be consulted.
Under questioning from Sir Keir, Mr Johnson confirmed that preparatory work to establish the inquiry’s terms of reference and its chair "will happen before the spring of next year".
"We will be getting it under way, we will be taking some key decisions," he added.
Liberal Democrat leader Sir Ed Davey said the PM and his government "have no end of questions to answer" about their handling of the pandemic.
"This coronavirus inquiry must have the teeth necessary to hold this government’s feet to the fire on their wrong-doings," he said.
"Lessons must be learnt from the mistakes that were made throughout this crisis and the government must be held to account for their handling of the pandemic."
The All-Party Parliamentary Group (APPG) on coronavirus said the delay in launching the inquiry would "prolong the pain being felt by grieving families and means vital lessons will go unlearned".