(CNN) The Congressional Budget Office raised its estimate of the projected federal budget deficit Wednesday and is now predicting that the deficit will reach $960 billion for the 2019 fiscal year, which ends on September 30, and reach $1 trillion for the 2020 fiscal year.
The CBO had previously estimated a $896 billion deficit for 2019 and $892 billion for 2020.
The Treasury Department reported earlier this month that the US budget deficit has already hit $867 billion for the first 10 months of the fiscal year, an increase of 27% over this time last year.
"The nation's fiscal outlook is challenging," said Phill Swagel, director of the CBO. "Federal debt, which is already high by historical standards, is on an unstainable course, projected to rise even higher after 2029 because of the aging of the population, growth in per capita spending on health care and rising interest costs."
He added that to put spending on a sustainable course, "lawmakers will have to make significant changes to tax and spending policies -- making revenues larger than they would be under current law, reducing spending below projected amounts, or adopting some combination of those approaches."
The White House's Office of Management Budget has run slightly higher numbers, predicting that the deficit will exceed $1 trillion for the entire fiscal year.
The country's debt has been piling higher under the Trump administration in part due to a $1.5 trillion tax cut signed into law in 2017 along with a massive spending package passed by Congress. Adding to the amassing heap is a two-year budget deal, signed by President Donald Trump, set to raise government spending by hundreds of billions of dollars.
Trump pledged to eliminate the federal debt during the 2016 campaign.
"CBO projects that the recent budget deal will add $1.5 trillion, plus interest, to our rapidly growing debt over the next decade," said Michael Peterson, CEO of the Peter G. Peterson Foundation in a statement. "That's on top of an already unsustainable outlook driven by major structural factors like demographics and rising health care costs."
The dismal economic forecast also comes as the President said his administration is weighing several tax cut proposals to help keep the economy moving. Doing so would only further reduce the government's revenue and add to the country's deficit.
"The recent budget deal was a budget buster, and now we have further proof," said Maya MacGuineas, president of the Committee for a Responsible Federal Budget, in a statement. "Both parties took an already unsustainable situation and made it much worse. Debt is now going to grow to almost the size of the economy within the decade. If Congress keeps extending tax cuts, debt will likely exceed the size of the economy within the decade.