Boris Johnson has set out a new target of 200,000 coronavirus tests a day by the end of May, as he admitted he "bitterly regrets" the crisis in care homes.
On his return to the Commons since his recovery from Covid-19 and his son's birth, the Prime Minister outlined the "ambition" to double testing "by the end of the month".
It comes after the Government fell short of its 100,000 a day target for the third day in a row.
Pressed on the shortfall by Labour leader Sir Keir Starmer, he said: "Yes, he’s right that capacity currently exceeds demand, we’re working on that, we’re running at about 100,000 a day, but the ambition clearly is to get up to 200,000 a day by the end of this month and then to go even higher."
The PM added that testing would be "absolutely critical" to the "long-term economic recovery" from the pandemic, having previously said he wants 250,000 tests a day.
Sir Keir replied: "I'm glad the Prime Minister has now said that the target is 200,000 tests a day by the end of this month. But of course just having a target isn't a strategy."
The PM admitted the continued reported shortages of personal protective equipment (PPE) on the front line was "enraging" but that Downing Street now had a "massive plan to ramp up domestic supply".
He also said he "bitterly regrets" the crisis in care homes, where staff have hit out at a lack of testing and PPE.
The latest figures show that nursing home fatalities are continuing to rise, standing at 2,794 in the week to April 24, despite deaths in all settings beginning to fall.
Health Secretary Matt Hancock initially pledged to hit the 100,000 mark by the end of April and said it had been achieved, but it emerged that about a third of the tests had not been processed by labs.
Ministers have been under fire since the daily rate dipped below 80,000 on Saturday, with 85,186 carried out on Sunday and 84,806 on Monday.
In other highlights from the first duel between Mr Johnson and his new opponent:
- The PM announced he would brief MPs about the Government's lockdown plans on Monday, warning it would be an "economic disaster" if a premature relaxation prompted a second peak of infections
- Mr Johnson said there had been a "palpable improvement" in the situation in care homes but that he "bitterly regrets" the outbreak hitting elderly residents
- Labour leader Sir Keir challenged the PM on the death toll nearing 33,000, the highest in Europe, adding: "So can the Prime Minister tell us how on earth did it come to this?"
- Mr Johnson replied: "Every death is a tragedy and he's right to draw attention to the appalling statistics, not just in this country but across the world"
- The pair also clashed over how accurate international comparisons of death tolls are, with Mr Johnson saying it is too early to conclusions.
It comes ahead of the PM's speech on Sunday night where he is expected to pave the way for the next phase of Britain's lockdown.
MPs questioned him during PMQs over why he is breaking normal Parliamentary protocol to not inform them of the eased measures first.
He said: "The reason for that is very simple, that we have to be sure the data is going to support our ability to do this.
"That data is coming in continuously over the next few days. We want if we possibly can to get going with some of these measures on Monday."