Donald Trump has sent Congress a $4.1 trillion spending plan that relies on faster economic growth and steep cuts to programmes for the poor in a bid to balance the government's books over the next decade.
The proposed 2018 budget immediately came under attack by Democrats and even some Republican allies who declared it dead on arrival.
The proposal is laced with cuts to domestic agencies, food stamps, Medicaid, highway funding and medical research.
Veteran House Republican Harold Rogers said: "These cuts that are being proposed are draconian. They're not mere shavings, they're deep, deep cuts."
The Senate's number two Republican, John Cornyn, said the plan joins a tradition of White House budgets that are "basically dead on arrival".
The proposal projects that this year's deficit will rise to $603 billion, up from the actual deficit of $585 billion last year, but the document says if Mr Trump's initiatives are adopted the deficit will start declining and reach a small surplus of $16 billion in 2027.
That goal depends on growth projections that most economists view as overly optimistic and a variety of accounting gimmicks, including an almost $600 billion peace dividend from winding down overseas military operations.
The government has not run a surplus since 2001 and deficits spiked during former president Barack Obama's first term in the aftermath of the Great Recession.
Mr Trump's new budget is based on sustained growth above 3%, sharply higher than the expectations of most private economists.
"The president believes that we must restore the greatness of our nation and reject the failed status quo that has left the American dream out of reach for too many families," the administration said in its budget, The New Foundation for American Greatness.
Mr Trump's plan cuts almost $3.6 trillion from an array of benefit programmes, domestic agencies and war spending over the coming decade - an almost 8% cut - including repealing and replacing Mr Obama's health law, cutting Medicaid, eliminating student loan subsidies, sharply slashing food stamps, and cutting $95 billion in highway formula funding for the states.
"We need people to go to work," White House budget director Mick Mulvaney told reporters at a briefing. "If you are on food stamps, we need you to go to work. If you are on disability and you should not be, we need you to go back to work."
Food stamp cuts would drive millions from the programme, while a wave of Medicaid cuts could deny nursing home care to millions of elderly poor people.
The Trump Administration budget slashes funding for the Environmental Protection Agency by nearly one-third, eliminating more than 3,800 jobs while imposing dramatic cuts to clean air and water programs.
The White House’s proposed spending plan for the EPA amounts to $5.7 billion, a 31 percent cut from the current budget year. Adjusted for inflation, that would represent the nation’s lowest funding for environmental protection since the mid-1970s.