CNN  — 

Despite severe shortages in coronavirus testing supplies and lags in results, the Trump administration is still sitting on billions of dollars in unused funding that Congress allocated months ago. Lawmakers on both sides of the aisle have questions about why the money has not been used as testing continues to fall well short of the national need.

“It’s probably a logistical problem as much as anything else, but yeah, it’s a concern,” said Republican. Sen. John Cornyn of Texas.

As negotiations have ramped up between the White House and Senate Republicans in recent days on whether to include more funding for testing in the next round of stimulus, the White House pushed against more money over the weekend, arguing that billions remain unspent. But lawmakers and aides – who estimate the remaining amount at about $7 billion to $8 billion – say they’ve been unable to get a clear answer to why that money hasn’t been touched in the first place.

In April, Congress passed legislation that included $25 billion in additional funds for testing and contact tracing. The money – which included $11 billion that went to states – was put into the Public Health and Social Services Emergency Fund at the Department of Health and Human Services. Months later, aides and lawmakers say they aren’t sure why so much still hasn’t been spent.

“They’ve never believed we should test,” Sen. Patty Murray, the top Democrat on the Health, Education, Labor and Pensions Committee, told CNN. “We’ve got to keep pushing.”

One Democratic aide familiar with discussions around the money said there was some speculation that it had been tied up at the Office of Management and Budget level, but there was no clear evidence whether the holdup had happened for any particular reason or was just a symptom of pushing billions out the door quickly.

Behind the scenes, lawmakers of both parties have asked the administration to explain why the money remains unused. Four Democrats on the Senate Appropriations Committee sent a letter directly to President Donald Trump this week asking for answers.

“In April, Congress appropriated $25 billion through the Paycheck Protection Program and Health Care Enhancement Act specifically to expand testing capacity and conduct surveillance and contact tracing to ensure we were prepared for another spike in cases. Yet based on the latest information from the Department of Health and Human Services, three months later less than half of the money provided has been obligated by the federal government and gaps in testing capacity and contact tracing are pervasive,” said the Democrats’ letter, signed by Murray along with Sens. Patrick Leahy of Vermont, Richard Durbin of Illinois and Jon Tester of Montana.

The letter also demanded that the administration explain why billions in funding to build up the Strategic National Stockpile hadn’t been used as reports show that states are once again struggling to find adequate personal protective equipment to weather the pandemic.

“Yet nearly four months later, the Administration has obligated only half of the funds Congress provided for the SNS (and only a portion of this was spent on PPE) and the Department of Defense has informed us that it intends to use nearly 70 percent of the DPA funding for shipbuilding, aircraft development, and other defense programs,” the letter reads, referring to the Defense Production Act.

Republicans have urged the administration in recent weeks to ramp up its response to the coronavirus as polls have shown the President lagging in key swing states and dragging rank-and-file Republicans up for reelection down with him.

“We have to up our game in testing. This is a worldwide problem,” Sen. Lindsey Graham, a South Carolina Republican who’s a close ally of Trump’s, told reporters Tuesday.

Republicans also strongly rebuked the administration’s argument that more funding wasn’t needed for testing and contact tracing in the next stimulus bill, saying that position not only put the country’s testing capabilities at risk, but also ignored the political realities of the situation.

“You would have to try hard to come up with a more tone-deaf position,” one GOP aide said over the weekend.

On Monday, members flat-out pushed back against the Trump administration’s position that more money for testing wasn’t needed.

“I just think that’s wrong,” said Sen. Roy Blunt, a Missouri Republican.