Labour party leader Keir Starmer has said coronavirus testing should have been carried out "much quicker" as he called on the government to publish its strategy on easing the current lockdown.
The newly elected leader told ITV's Peston that under him the Labour party would "support the government where it was right to do so" but also have "the courage to challenge them where they were getting wrong."
In response to ITV News Political Editor Robert Peston's questions about whether the government had been too slow to roll out Covid-19 tests, Mr Starmer said: "We should have ramped up testing much, much more quickly."
"I think there are things to learn from Germany as a result of that. And we do need to ask probing questions of the government about that."
But he said now was not the time for "quipping" from the Labour benches about "what should have been done".
"At the moment what we want to do is to make sure we actually get that testing," he said.
The government has so far not released any details on how and when the coronavirus restrictions will be lifted, fearing people would not follow the strict social distancing rules currently in place.
Sir Keir said it was "important for the government to set out" what the strategy was.
"Because as I see it, a vaccine is obviously the long term solution but it looks like that won't be ready for 12 to 18 months.
"And therefore all the focus is on testing," he said.
Sir Keir continued: "The one (test) that tells you whether you've got it is, I hope, going to be available in much greater numbers, that's what the government have committed to."
But he said the problem with the test that shows whether you have the virus or not was only a way of "controlling things" and "not a way out".
Sir Keir refused to rule out forming a national government with the government to see the country through the coronavirus crisis. He said he had been fully briefed on the coronavirus situation since his election.
"Within an hour of being elected I had a conversation with the Prime Minister about the arrangements that we would put in place. I asked for confidential briefings on a privy council basis from the experts on a one-on-one basis and for access to ministers on the same basis.
"The Prime Minister agreed to that. I told him that the Labour party under my leadership would be constructive and pull together in the national interest and that meant having the courage to support the government where it was right to do so. But also having the courage to challenge them where they were getting wrong or they were going too slowly."
Sir Keir denied purging the Corbynistas from his shadow cabinet, saying the new team "comes from all bits of the party".
"It's a very diverse team with representatives from across the United Kingdom. It's a very exciting talented team going forward and I can tell you, Robert, that the feeling of the Labour Party coming together has been palpable over the last few days. There's a real energy and spirit of hope in what we're doing."
ITV News Political Editor's show Peston airs every Wednesday on ITV at 10.45pm.