Boris Johnson was interrupted as he apologised for the “suffering” caused by the COVID pandemic.
Four people were subsequently removed from the hearing, where they had been in the public gallery holding up pictures.
Mr Johnson told the inquiry: “I am deeply sorry for the pain and loss and suffering.”
One protester held up a poster reading: “The dead can’t hear your apologies.”
Mr Johnson went on to say he hoped the inquiry was able to “get answers to those very difficult questions” victims and their families are “rightly asking”.
Boris Johnson COVID evidence live: Former PM apologises to victims as he begins marathon evidence session at inquiry
The evidence session also heard:
• The government “underestimated the scale and pace of challenge” from COVID – thinking the peak would come in May or June;
• The tone of the private WhatsApps was a “reflection of the agony” the country was going through;
• Mr Johnson takes “full responsibility” for decisions made;
• Mr Johnson only read Scientific Advisory Group for Emergencies (Sage) minutes “once or twice”
Watch a Sky News special on Johnson’s day of evidence at 9pm
The former prime minister was speaking on the first day of his appearance at the official COVID inquiry he set up in order to learn the lessons of the pandemic for the future.
He is the inquiry’s most highly anticipated witness and follows on from fellow politicians including former health secretary Matt Hancock, former deputy prime minister Dominic Raab and Levelling Up Secretary Michael Gove.
The inquiry, which is now examining decision-making and political governance, began with Baroness Hallett raising issue with the briefings ahead of Mr Johnson’s appearance, arguing that a leak “undermines the inquiry’s ability to do its job fairly, effectively and independently”.
Mr Johnson will be questioned for two days about decisions he made which took the country into three national lockdowns.
‘Should things have been done differently? Unquestionably’
The former prime minister told Hugo Keith KC, lead counsel for the inquiry, that “unquestionably” mistakes were made by his government during the pandemic, adding that he took “responsibility for all the decisions that we made”.
Pressed on what mistakes he felt were made, Mr Johnson cited communications and the different messaging coming from the different governments in the UK.
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COVID families don’t want Johnson ‘waffle’
Mr Johnson also said he took responsibility for the speed of the government’s response to the pandemic, the lockdown decisions and their timeliness, the circulation of the virus in the residential care sector and the Eat Out to Help Out scheme.
He said he acknowledged that “so many people suffered, so many people lost their lives”, the government was “doing our best at the time, given what we knew, given the information I had available to me at the time, I think we did our level best”.
Mr Keith KC ten turned to questioning Mr Johnson on why he did not forsee the scale of destruction the the COVID pandemic would cause in early 2020, given that
Mr Johnson admitted that the wider government “underestimated” the threat posed by the virus, saying the “concept of a pandemic did not imply to the Whitehall mind the kind of utter disaster that COVID was to become”.
He said in the “early days of March”, government figures and officials “were all collectively underestimating how fast it had already spread in the UK”.
“We put the first peak too late, we thought it would be May/June – that was totally wrong. I don’t blame the scientists for that at all.
“That was the feeling and it just turned out to be wrong.”
Johnson questioned on 5,000 missing WhatsApps
In the days leading up the inquiry there were reports anticipating Mr Johnson’s apology and the fact that not all of his WhatsApps would be made available to the inquiry – with about 5,000 messages on his phone from January 30, 2020 to June 2020 missing.
Mr Johnson said he did not know the “exact reason” they were not located, but said it was” something to do with the app going down and then coming up again, but somehow automatically erasing all the things between that date when it went down and the moment when it was last backed up”.
Mr Keith said a technical report provided by the former prime minister’s solicitors suggested there may have been a factory reset on the phone at the end of January 2020 followed by an attempt to reinstall its contents months later in June – something Mr Johnson said he did not remember.
“Can I, for the avoidance of doubt, make it absolutely clear I haven’t removed any WhatsApps from my phone and I’ve given you everything that I think you need?” he said.
As well as politicians appearing before the inquiry, other figures that have given evidence include top scientists at the time – including Chief Medical Officer Chris Whitty and former chief scientific adviser Sir Patrick Vallance – and Mr Johnson’s former chief adviser Dominic Cummings.
Mr Cummings has previously given evidence to the inquiry in which he described Downing Street as in a state of “complete chaos” and claimed that he urged Mr Johnson to remove Mr Hancock – whom he claimed “lied his way” through the pandemic.
Read more:
COVID inquiry: Michael Gove apologises for pandemic ‘errors’
COVID inquiry about ‘scapegoating’ senior government figures, Boris Johnson’s sister says
Government had ‘challenging and competing characters’
Mr Keith told Mr Johnson that the WhatsApp messages that have been shown to the inquiry “paints an appalling picture, not all the time but at times, of incompetence and disarray”.
Mr Johnson argued that plenty of successful governments have “challenging and competing characters whose views about each other might not be fit to print but who get a lot done”.
Asked about comments he made in which he called Mr Hancock “totally f***** useless”, Mr Johnson replied: “My job was not uncritically to accept that everything we were doing was good. I do think that the country as a whole had notable achievements during the crisis.”
He admitted that while he was aware Mr Cummings had a “low opinion” of the health secretary, he thought Mr Hancock “worked very hard, he had defects, but I thought that he was doing his best in very difficult circumstances”.