The UK government has “over-promised and under-delivered” as it deals with coronavirus, a former head of the civil service is to argue in a speech later.
Lord O’Donnell will say “strategy” and “leadership” have been lacking.
And he will say PM Boris Johnson used “political capital” by keeping senior aide Dominic Cummings in place after his long drive north during lockdown.
The government said its “clear” strategy was to save lives, while protecting the economy and education.
This week it tightened up rules in England on the size of social gatherings, pub and restaurant opening hours, and the use of face coverings.
The changes came amid a rising infection rate and after the government’s two most senior pandemic advisers warned there could be 50,000 cases a day by October.
Meanwhile, the number of daily recorded UK Covid-19 cases rose by a quarter to 6,178 on Wednesday.
In his speech to the Institute for Fiscal Studies think tank, Lord O’Donnell will say: “We have to ask why a country with such reputed health and intelligence institutions has been so incapable of combating the Covid-19 pandemic.”
The crossbench peer - who served as cabinet secretary under prime ministers Tony Blair, Gordon Brown and David Cameron - will add: “A litany of new rules and a steady stream of leaks reflects a government struggling to emerge from firefighting mode.
“Without a clear strategy, strong leadership and the use of good evidence from a range of human sciences, there is a risk that our efforts to emerge from this pandemic will be protracted and extremely costly.”
Lord O’Donnell will also say: “In addition to some operational failings, ministers have frequently broken one of the cardinal rules: they have over-promised and under-delivered.”
The new coronavirus measures have divided opinion among scientists, with some claiming they do not go far enough but others saying they are a shift towards more coherent policy.
He said there would always be the “Goldilocks criticism” of the government - that it was doing “too much or too little”.
It emerged during lockdown that Mr Johnson’s most senior adviser, Mr Cummings, had driven from London to County Durham with his wife and child.
There were calls to sack Mr Cummings and claims he had broken the law, but he insisted he had acted “reasonably” and lawfully.
Mr Johnson, who himself had been hospitalised by Covid-19 earlier in the crisis, backed his aide and he kept his job.
In his speech, Lord O’Donnell will say the prime minister “used up his political capital” in doing so.
A government spokesperson said: “Throughout the pandemic the government has taken advice from a wide range of scientific and medical experts.
“At every stage we have struck a delicate balance between saving lives by protecting our NHS and minimising the wider impact of our restrictions.”