Photo: The Canadian Press

President Donald Trump unveiled a $1.15 trillion budget on Thursday, a far-reaching overhaul of federal government spending that slashes many domestic programs to finance a significant increase in the military and make a down payment on a U.S.-Mexico border wall.

Trump's proposal seeks to upend Washington with cuts to long-promised campaign targets like foreign aid and the Environmental Protection Agency as well as strong congressional favourites such as medical research, help for homeless veterans and community development grants.

"A budget that puts America first must make the safety of our people its number one priority — because without safety, there can be no prosperity," Trump said in a message accompanying his proposed budget that was titled "America First: A Budget Blueprint to Make America Great Again."

The $54 billion boost for the military is the largest since President Ronald Reagan's Pentagon buildup in the 1980s, promising immediate money for troop readiness, the fight against Islamic State militants and procurement of new ships, fighter jets and other weapons. The 10 per cent Pentagon boost is financed by $54 billion in cuts to foreign aid and domestic agencies that had been protected by former President Barack Obama.

The budget goes after the frequent targets of the party's staunchest conservatives, eliminating the National Endowment for the Arts, legal aid for the poor, low-income heating assistance and the AmeriCorps national service program established by former President Bill Clinton.

"This is a hard power budget, not a soft power budget," said White House budget director Mick Mulvaney.

Law enforcement agencies like the FBI would be spared, while the border wall would receive an immediate $1.4 billion infusion in the ongoing fiscal year, with another $2.6 billion planned for the 2018 budget year starting Oct. 1.

Trump repeatedly claimed during the campaign that Mexico would pay for the wall when, in fact, U.S. taxpayers will foot the bill.

Twelve of the government's 15 Cabinet agencies would absorb cuts under the president's proposal. The biggest losers are Agriculture, Labor, State, and the Cabinet-level EPA. The Defence Department, Department of Homeland Security and Department of Veterans Affairs are the winners.

Trump's proposal covers only roughly one-fourth of the approximately $4 trillion federal budget, the discretionary portion that Congress passes each year. It doesn't address taxes, Social Security, Medicare and Medicaid, or make predictions about deficits and the economy. Those big-picture details are due in mid-May. Trump has vowed not to cut Social Security and Medicare and is dead set against raising taxes.