The head of Test and Trace has said she doesn't believe "anybody was expecting to see the really sizeable increase in demand" for coronavirus tests.
Baroness Dido Harding's admission came after some residents in COVID-19 hotspots complained they were finding it difficult to get tested.
Reports have poured in of people saying they were told tests were unavailable or had to be done hundreds of miles away from where they live.
Greg Clark, a Tory MP who chairs the Commons Science and Technology Committee, said: "It is dispiriting to find that we are now in September, in circumstances which are entirely predictable – people are going back to school, people are going back to work – and we haven't had the right capacity put in place during the quieter times of June, July and August."
He told Baroness Harding when she gave evidence on Thursday: "Clearly you didn't prepare enough."
The head of Test and Trace insisted that it had not been a "quiet summer" but admitted: "Plainly we don't have enough testing capacity."
Baroness Harding also confirmed that key workers are going to be prioritised for coronavirus tests – with teachers "likely to be top of that list" so schools can "remain functioning".
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She added that about 50% of tests are being reserved for hospital patients, social care staff and residents, and NHS workers – including GPs and pharmacists.
The Conservative peer partially blamed the big rise in demand on schools reopening, revealing the number of children asking for tests has doubled – and grew at an even higher rate among those aged five to nine years old.
And she confirmed the current daily test capacity is 242,000 – though not all of this capacity is being used.
The next target is 500,000 a day by the end of October, but Baroness Harding refused to say if that would be enough.
"I am certain we will need more as we go beyond the end of October," she said.
Baroness Harding also suggested the failure to give everyone their test result in 24 hours was deliberate – to not put too much strain on labs.
"We made a conscious decision, because of the huge increase in demand, to extend the turnaround times in oRead More – Source