WASHINGTON (AFP) - US President Donald Trump in mid-March will unveil his first government budget, a keystone statement of his priorities for the coming years, the White House said on Wednesday (Feb 22).

The nearly four trillion dollar annual federal budget is a declaration of intent that puts the President's policy goals down in black and white.

It also separates affordable campaign promises from the fanciful and is the final arbitrator after turf wars between departments and powerful interest groups.

"We'll have something in mid-March," said White House spokesman Sean Spicer.

Trump huddled with budget advisors early on Wednesday to rake through the proposals.

At the meeting, Trump repeated his campaign rhetoric about cutting waste and renegotiating federal contracts.

"The finances of this country are a mess but we're going to clean that up," he said.

US president after US president has made similar promises on coming to office, before delving into a text that runs in the thousands of pages and tossing the plan into the thicket of Congress.

Trump has oodles of campaign promises to pay for, but faces a national debt set to hit US$20 trillion (S$28 trillion) on his watch and a deficit at 3.1 per cent of GDP and rising.

Trump's promises - from building a wall on the Mexican border to deporting undocumented immigrants - carry an estimated price tag of US$5.3 trillion, according to the non-partisan Committee for a Responsible Federal Budget.

Trump tried to give himself some cover for criticism of the upcoming plan.

"We're going to take this budget, which is in all fairness I've only been here for four weeks, so I can't take too much of the blame for what's happened but it is absolutely out of control," Trump said.