Sir Keir claimed Mr Sunak had stood in the way of a two week shutdown when it was first recommended by Government experts as he attacked ministers for failing to move quicker ahead of the imposition of an England-wide lockdown from Thursday.
He said the delay in introducing new national restrictions means 'businesses have to close for longer' and 'more people will lose their jobs'.
Warning of the 'severe' consequences now facing many businesses across the country, Sir Keir added: 'Make no mistake, the Chancellor's name is all over this.'
His comments to the Confederation of British Industry (CBI) conference came as business bosses warned they are now facing a 'bleak' winter.
Meanwhile, Business Secretary Alok Sharma told the same event that the use of rapid coronavirus tests could provide a way out of the current crisis as he acknowledged a fully functioning vaccine 'may never materialise'.
Sir Keir Starmer today accused Chancellor Rishi Sunak of 'blocking' a 'circuit breaker' lockdown when one was first recommended by experts in September
Sir Keir claimed the Chancellor had 'failed' in his coronavirus response and as a result 'more people will lose their jobs'
Sir Keir's intervention came as experts predicted the UK is heading for a double dip recession with GDP forecast to shrink by up to eight per cent in the final quarter of 2020
Sir Keir addressed the CBI conference after economists predicted the second national lockdown will cause a double dip recession, with UK GDP forecast to shrink by as much as eight per cent in the final quarter of 2020.
The Labour leader said he does not 'blame the Government for coronavirus but I do blame it for the way it's been handled'.
He said he could not forgive the 'catalogue of mistakes that have cost lives and livelihoods' as he claimed the Prime Minister and the Chancellor had both 'failed to learn' and 'failed to listen'.
Labour has been calling for a national lockdown for weeks and Sir Keir said the Government's latest U-turn is 'better late than never'.
But he added: 'The central lesson of the first wave was ignored: That if you are to control this virus you have to act early and decisively and that if you don't the cost to people's health and to the health of the economy is much, much worse.
'One of the things I've learnt from this crisis is that it exposes leadership like nothing else.
'On that count the Prime Minister and the Chancellor have failed. They failed to learn. They failed to listen. And they failed to lead. The result is tragic – but all too predictable.'
Sir Keir cited the fact that the Government's Scientific Advisory Group for Emergencies (SAGE) had recommended a two to three week 'circuit breaker' lockdown on September 21.
The Labour leader said on that day there were 11 deaths from Covid-19 and 4,000 new infections but Mr Johnson and Mr Sunak 'failed to heed that warning'.
He continued: 'Forty days later when he finally decided to announce a longer four-week national lockdown –those figures had increased to 326 deaths a day, and 22,000 Covid cases. That is the human cost of the Government's inaction.
'And the impact on business – and jobs – will be severe. Make no mistake, the Chancellor's name is all over this.
'His decision to block a circuit breaker, to dismiss it as a "blunt instrument" and to pretend that you can protect the economy without controlling the virus will now mean that businesses have to close for longer, more people will lose their jobs, and the public finances will be worse than they needed to be.
'It makes me so angry and so frustrated that when the British people – and British businesses – have given so much and made so many sacrifices, they have been let down so badly by the Government.'
Sir Keir's intervention came as CBI director general Dame Carolyn Fairbairn condemned the way the Government has handled major coronavirus announcements, with details emerging via leaks and briefings to the press.
She said firms could not act on the basis of 'speculation and leaks and surmise', demanded more clarity on the Government's strategy and called for ministers to improve the coronavirus testing system.
The outgoing CBI chief said England's second lockdown will be 'truly devastating for business', with many companies having already invested millions of pounds to make their premises 'Covid-secure'.
She said they face a 'bleak' winter, adding: 'This is the run-up to Christmas, it's the most important time for so many firms.'
Mr Johnson had been due to address the conference but he pulled out as he wrestled with the Government's latest coronavirus chaos.
Outgoing CBI director general Dame Carolyn Fairbairn today warned many firms are facing a 'bleak' winter because of the Government's decision to impose a second national lockdown
Boris Johnson had been due to address the CBI conference but he sent Business Secretary Alok Sharma in his place
It is only the second time in the CBI's 55 year history that the serving prime minister has not addressed the summit.
Mr Johnson sent Mr Sharma in his place and the Business Secretary admitted the second lockdown in England is 'regrettable'.
But he insisted the Government would continue to support struggling businesses and workers, and he promised that ministers had a long-term plan to build a more resilient economy as the country emerges from the pandemic.
Mr Sunak suggested that rapid testing for Covid-19, with results processed in as little as 15 minutes, could provide a route out of lockdown restrictions.
He told the conference: 'As the Prime Minister set out on Saturday, we have the immediate prospect of using many millions of cheap, reliable and rapid-turnaround tests.
'Over the next few days and weeks, we will plan a steady but significant deployment of these tests.
'There are paths out of this current predicament to eventually get business fully on its feet and the economy firing on all cylinders.'