Governors across the country Sunday pushed back on the Trump administration's claims that states are conducting a "sufficient" level of coronavirus testing.

Speaking with CNN's "State of the Union," Virginia Gov. Ralph Northam, a Democrat, said it was "delusional" to suggest that the states have enough tests to begin reopening their economies soon.

"That's just delusional to be making statements like that. We have been fighting every day for PPE," Northam said, referring to personal protective equipment. "And we have got some supplies now coming in. We have been fighting for testing. It's not a — it's not a straightforward test. We don't even have enough swabs, believe it or not. And we're ramping that up. But for the national level to say that we have what we need and really to have no guidance to the state levels is just irresponsible, because we're not there yet."

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Maryland Gov. Larry Hogan, a Republican, said on CNN that the "lack of testing" is "probably the number one problem in America and has been from the beginning of this crisis."

"And I have repeatedly made this argument to the leaders in Washington on behalf of the rest of the governors in America," Hogan said. "And I can tell you I talk to governors on both sides of the aisle nearly every single day. The administration, I think, is trying to ramp up testing and trying — they are doing some things with respect to private labs. But to try to push this off, to say that the governors have plenty of testing and they should just get to work on testing, somehow we aren't doing our job, is just absolutely false."

He added that governors have been "fighting and clawing to get more tests" from both the federal government and private labs and are continuing to do so. He echoed Northam in saying there are shortages of swabs to conduct the tests, among other necessities.

"So, look, I think they have made some strides at the federal level," Hogan said. "I think states are all working hard on their own to find their own testing. Lab capacity has been increasing. But it's not accurate to say there's plenty of testing out there and the governors should just get it done. That's just not being straightforward."

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Public health experts have said testing would need to at least double or even triple to allow even a partial reopening of America's economy. Without such a massive increase, officials will lack a clear picture of who is infected, who can safely return to work, how and where the virus is spreading and whether stay-at-home orders can begin to be eased, those experts said.

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President Donald Trump insisted later Sunday that "I am right on testing."

"Just like I was right on Ventilators (our Country is now the 'King of Ventilators', other countries are calling asking for help-we will!), I am right on testing," he said in a tweet. "Governors must be able to step up and get the job done," he continued. "We will be with you ALL THE WAY!"

Later Sunday, Trump announced he would invoke the Defense Production Act to compel companies to ramp up production of swabs — something governors had pushed for.

The White House's own recommendations, revised last week, note that robust testing is needed for states to begin easing coronavirus restrictions. The White House has said that testing will be state-led and that it believes enough tests are available for any state to move into the first phase of reopening.

Vice President Mike Pence said Sunday that the U.S. had completed 4 million tests as of Saturday (a number that represents slightly more than 1 percent of the country). Pence said the U.S. can test 150,000 people per day, although daily capacity would double "overnight" if states would reactivate all of their labs that can handle tests.

"There is a sufficient capacity of testing across the country today for any state in America to go to a Phase 1 level, which contemplates testing people that have symptoms of coronavirus, and also doing the kind of monitoring of vulnerable populations in our cities, in our nursing homes, that we ought to be watching very carefully for outbreaks," Pence said on NBC News' "Meet the Press."

The White House's coronavirus response coordinator, Dr. Deborah Birx, said on CBS' "Face the Nation": "The numbers originally said that we only needed 750,000 tests a week. We've long since passed that. The new number coming from Harvard is the half a million a day.

"What we're trying to do is look at this in a very data-driven, granular scientific methodologies to protect community by community the testing that is needed," she continued. "At the same time, working with every laboratory director across the country that have these multiple platforms to really understand and find solutions for them on their issues related to supplies."

But governors have said they are short of the necessary equipment to conduct widespread testing. Speaking on "Meet the Press," Ohio Gov. Mike DeWine, a Republican, said he "could probably double, maybe even triple testing in Ohio virtually overnight if the FDA would prioritize companies that are putting a slightly different formula together for the extraction reagent kit."

"If anyone at the FDA is watching, this would really take our capacity up literally overnight, and that's what we need to get moving in Ohio," he added.

Gov. Gretchen Whitmer, a Democrat, said Michigan also has the capacity to "double or triple the number of tests we are doing, but we need some of the supplies."

"The reagents and the swabs are absolutely essential," she said. "You can't process all these tests if you can't take the sample and protect it. And move forward through testing. So while our capabilities are there, these important supplies are not."

She said that if the federal government could use the Defense Production Act to have companies make swabs and hasten the creation of the reagents, "we would be able to know how prevalent COVID-19 is."

"It would take down the risk associated with taking actions to re-engage parts of our economy, because we would have a lot more data about how prevalent COVID-19 still is in our states," she added.

House Speaker Nancy Pelosi, D-Calif., said on "Fox News Sunday" that testing is "part of something bigger" that has to "be done properly." She said testing must be joined by a program of contact tracing, treatment and individual quarantines to be effective.

"We're way late on it," Pelosi said of widespread testing. "And that is the failure. President gets an 'F,' a failure, on the testing."