WATCH: White House COVID coordinator warns of a surge in winter

The White House COVID-19 coordinator issued a dire warning Thursday about the nation’s ability to battle a potential pandemic surge this fall if Congress fails to provide billions more dollars to brace for the next wave.

Watch the briefing in the player above.

Speaking at the White House briefing, Dr. Ashish Jha said the government purchased a large amount of both vaccines and therapeutics that will get the country through the summer, even with rising case numbers.

But he warned, those tools will begin to run out by the fall and winter, a time when some models show there could be “a sizeable wave of infections.”

“That’s where I start getting very, very concerned. I mean, you want to ask what keeps me awake at night? It is that we are going to run out of vaccines,” Jha said.

“We’re not going to able to have enough of the next generation of vaccines. We are going to run out of treatments and we’re going to run out of diagnostic tests probably in the late fall into winter if we end up having a significant surge of infections. We don’t have the resources to buy those things. And those purchases need to be made now,” he underscored.

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The White House appeal for funds for vaccines, testing and treatments has hit opposition from Republicans, who’ve fused the fight with the precarious politics of immigration.

House and Senate Democrats have been wrangling over how to resolve the stalemate and even over which chamber should vote first. It’s an open question whether they’ll ever get the GOP votes they’ll need to pull the legislation through the 50-50 Senate, and prospects in the narrowly divided House are unclear as well.

Optimists hope the measure could start rolling once Congress returns next week. Pessimists say without quick resolution, Democrats may not have enough leverage to push the money to passage until early fall. That’s when they could stuff it into legislation that will probably be needed to finance government – a bill that would avert a federal shutdown, a pre-election distraction Republicans will be desperate to avoid.

Congress has provided $370 billion for purchasing supplies, for research and other public health initiatives to combat the pandemic, according to administration tallies obtained by The Associated Press.

Around $14 billion of it was unspent or not committed to contracts as of April 5, the documents show, serious money but an amount the administration says falls below the ultimate need.