Health Secretary Matt Hancock has set a new target to carry out 100,000 coronavirus tests a day by the end of the month.
He laid out his plan to expand the number of tests for NHS workers after fury over the small number of staff checked for coronavirus.
But the 100,000-a-day target includes both antigen tests - which show if you currently have Covid-19 - and antibody tests - which show if you had it in the past. The previous target of 25,000 was just antigen tests, the ones most in demand right now.
Mr Hancock said several tests pitched to the Government have failed checks, with one missing three out of four cases of coronavirus.
He also announced that £13.4billion of debt at NHS trusts across the country is being written off to help them dealt with the coronavirus pandemic.
Speaking at today's Downing Street press conference, he said: "I am now setting the goal of 100,000 tests per day by the end of this month. That is the goal and I am determined that we will get there.
"All the front line NHS staff who need tests will get them by the end of this month.
"We are in the midst of a war against an invisible enemy. And it is a war in which all of humanity is on the same side.
"Mass testing is how we unlock the coronavirus puzzle and defeat it in the end."
Mr Hancock said the government's previous 25,000-a-day antigen tests had been promised by the end of April “at the latest”.
In fact, it was pledged for the middle of April, not the end. A government statement on March 18 said: "The increased capacity is expected to be ready within 4 weeks."
He also explained that the Government had rejected certain coronavirus tests because they were not effective.
Mr Hancock said: “Several of the tests we’re currently checking have failed. In one case a test I’m being urged to buy missed 3 out of 4 cases of coronavirus.
“Approving tests that don’t work is dangerous and I will not do it.
“I can announce I’m waiting off £13.4bn of historic NHS debt.
“This landmark step will not only put the NHS in a stronger position to be able to respond to this global coronavirus pandemic, but it will also ensure our NHS has stronger foundations for the future too.”
Earlier today the government admitted its coronavirus testing regime does not go far enough after days of anger at the slow progress on checks for Covid-19.
Boris Johnson's official spokesman accepted "we need to make progress very quickly" after officials repeatedly failed to meet the UK's capacity for daily tests.
Downing Street said Health Secretary Matt Hancock will announce a "significant increase in testing" later on, likely at the daily press conference.
The PM's spokesman told journalists: "We acknowledge that more needs to be done.
"We agree we need to be testing more people and to make progress very quickly.
"The Health Secretary will set out our plans for a significant increase in testing later on."
Downing Street was forced to deny a "blame game" after issuing a clear instruction to medics to test more NHS staff - only for them to complain they were held back by red tape.
Public Health England Medical Director Paul Cosford admitted: "Everybody involved is frustrated that we haven't got to the position yet that we need to get to."
Yesterday the government said 2,000 NHS staff had been tested - despite claims more than 100,000 are off sick or self-isolating.
Earlier today Downing Street clarified that the number was in fact higher than previously said.
No10 said there were actually two strands of testing for NHS staff - drive-through tests, which had tested 2,800 staff, plus testing within NHS labs of frontline staff.
The Government said this second section has tested a "significant number" of NHS staff.
Meanwhile a new lab in Milton Keynes has now started taking samples from NHS staff, No10 claimed.
Downing Street said nearly 100 universities, companies and research institutes agreed to lend their machines for the Milton Keynes effort and "not a single institution that was asked refused”.
Boris Johnson last night said testing "is how we unlock the coronavirus puzzle and defeat it in the end”.
His spokesman said today: "Testing is so important, not least because it means people can go forward with confidence that they can’t be infected or be infectious."
But hopes to clear an antibody test - of which the UK has bought 3.5million of different types - for use have so far gone unfulfilled.
Unlike the current antigen test, which shows if you currently have Covid-19, an antibody test will show if you had it in the past and now have some immunity.
The PM's spokesman admitted: "Tests have been supplied to us that have not met the required level of accuracy and therefore would have not be safe to use."
However, he could not give further detail. "As soon as a test is approved we will announce it publicly," he said.
Downing Street also faced anger over the availability of protective equipment for NHS staff.
Boris Johnson's spokesman said 5million aprons, 1million FFPE3 face masks, 6million surgical masks and 21million gloves had been distributed to staff recently.
But he admitted: "We do recognise there have been some distribution problems while we have been dealing with a surge in demand. We are confident enough supply is now reaching the front line.”
Meanwhile, Downing Street refused to rule out tightening the lockdown even further if people start flouting restrictions.
Boris Johnson’s spokesman said: “The Prime Minister has said we will at all times follow the scientific and medical advice and if we need to take further steps we won’t hesitate to do so.”
And No10 refused to confirm or deny whether it used mobile phone location data to decide on a lockdown last week.
The PM’s spokesman said: “What I’ve said is more broadly we’ve received data from a wide variety of sources in relation to protecting people’s health, but at all times we follow data protection rules.”
Asked why he couldn’t confirm about phone data he said: “I have no more for you on this. We have been over it a number of times. I’ve said what I’m in a position to say.”
