The government is aiming to carry out 100,000 coronavirus tests a day in England by the end of April, Health Secretary Matt Hancock said, as he announced a "five-pillar" testing plan.
It comes as the government was criticised for not increasing the number of tests more quickly.
Currently, there are around 10,000 tests being carried out a day.
The new target includes swab tests, which are already in use, and blood tests, which are yet to be launched.
It was originally thought the target would be for the whole of the UK, but the government later issued a correction saying the goal will only be for England.
The number of people with the virus who have died in the UK has risen by 569, taking the total to 2,921 as of 17:00 BST on Wednesday.
Speaking at the end of his seven days of quarantine after testing positive for the virus, Mr Hancock said 100,000 tests "is the goal and I'm determined we'll get there".
The five points in Mr Hancock's plan, which are designed to combine to deliver the new target, are:
- Swab tests - to check if people already have the virus - in labs run by Public Health England
- Using commercial partners such as universities and private businesses like Amazon and Boots to do more swab testing
- Introducing antibody blood tests to check whether people have had the virus
- Surveillance to determine the rate of infection and how it is spreading across the country
- Building a British diagnostics industry, with help from pharmaceutical giants
Mr Hancock said that the UK wants to buy 17.5 million antibody tests, "subject to them working".
He added that the government was working with nine companies who have offered the blood tests - but he added "they have got to work" and the government will not allow them to be rolled out if they are not effective.
Labour's shadow health secretary Jonathan Ashworth welcomed the new target but said it was "not the 250,000 Boris Johnson promised". Mr Hancock said the government still hopes to get to 250,000.
Mr Ashworth also called for more clarity and details, asking how many of the 100,000 tests will be blood tests, and what role testing will play in the government's "exit strategy" to end the lockdown.
On Wednesday, there was capacity for 12,799 daily tests in England - although just 10,650 people were tested. The government's target by mid-April had been to test 25,000 per day.
Latest figures show 163,194 people in the UK had so far been tested for the virus, of which 33,718 were confirmed positive.
Key questions remain
After days of mounting criticism, the five-point testing plan was an attempt to reassure the public the government is on top of the issue.
But key questions remain. There are basically two broad types of tests despite the five separate points - one to diagnose the presence of the virus and one to identify whether an individual has had it in the past (the so-called antibody test).
In the coming week or two, the diagnostic test is the priority. Staff need access to them to allow them to return to work if they fear they have or their household members have symptoms.
In the longer-term, the antibody test comes into play. The big unknown is how many people have been exposed to the virus without knowing it because they did not show symptoms.
There are suggestions as many as half of infected cases may fall into this category. That could be vital in deciding what to do once the impact of lockdown is felt in falling numbers of cases and deaths.
If there has been widespread infection it reduces the likelihood of a second wave and continued spread of the virus.
The problem is the ability to hit the goal set - 100,000 tests a day - is out of the government's hands.
A global shortage of the chemicals and kits for the diagnostic test is a serious difficulty.
What is more, there are no guarantees the antibody tests the UK government is looking to use will work.
Mr Hancock also said there had been problems with some tests being inaccurate. "In one case a test that I'm being urged to buy missed three out of four positive cases for coronavirus," he explained.
"That means that three-quarters of cases, that test would have given the false comfort of sending someone with coronavirus back on the wards. Approving tests that don't work is dangerous and I will not do it."
Earlier, senior health officials said they were "frustrated" by the UK's lack of progress in expanding testing, and the current figures were "nowhere near where we need to get to".
Some critics pointed out the UK was well behind countries like Germany in testing, but Mr Hancock said the UK "didn't go into this crisis with a huge diagnostics industry" like other countries.
What are the tests for coronavirus?
There are two main types of coronavirus test that are useful in fighting the epidemic:
The antigen or "have I got coronavirus now?" test will tell you if someone is currently infected and risks spreading it to others. That's the one that is being used to check very ill patients in hospitals and will now be rolled out to NHS staff too.
The antibody or "have I recently had coronavirus" test is not available to the public yet but Public Health England is ordering it in the millions and will distribute it as soon as they are confident about its accuracy. That would help tell us how many people got coronavirus with no or only mild symptoms.
Both are vital to get a better handle on how to stop the spread of this deadly disease.
NHS England medical director Stephen Powis told the briefing there were "reasons to be hopeful" - including that there is early evidence the transmission rate had fallen to below one, meaning each infected person infects less than one person.
"That's important because if it's the case that we are no longer passing the virus on to multiple people, so to less than one person for everyone who is infected, then that is additional evidence that infections are going to reduce," he said.
But he added people should not become complacent, adding that they are "reasons to continue" with the social distancing measures.
The warning came hours before the number of confirmed infections globally passed one million, according to the latest figures from Johns Hopkins University.
Also announced at the press briefing:
- The government was writing off £13.4bn of historic NHS debt, so that hospital trusts are in a "stronger position" to deal with the outbreak
- Premier League footballers should take a pay cut to help the UK respond to the crisis, Mr Hancock said, adding that: "Everyone needs to play their part." It comes after some clubs were criticised for using a government scheme to cut the salaries of non-playing staff, while paying players in full
- Public Health England has updated its guidance on when staff should wear personal protective equipment
- The government is considering issuing immunity certificates to those shown to have had the virus - but Mr Hancock added that it was "too early in the science" to give further details
- Mr Hancock credited the Labour Party for some of the government's financial measures, saying ministers listened and "took those steps"
- Around 8% of all NHS England staff, and 5.7% of all doctors, are off work because of coronavirus-related reasons