Factbox: Key points of Trump's 2018 budget proposal

MAIN STORY - Trump's first full budget would slash funding for healthcare and food assistance programs that help the poor while it trims the deficit. The plan - if agreed to by Congress - would cut $3.6 trillion in government spending over 10 years, balancing the budget by the end of the decade. More than $800 billion would be cut from the Medicaid program for the poor, and more than $192 billion from food stamps.

THE WALL - Trump is asking Congress for $1.6 billion for fiscal 2018 to begin building a wall along the border with Mexico, far short of the amount needed for a project sharply criticized by Democrats and even some conservative Republicans. An internal Department of Homeland Security plan has estimated the wall's total cost at $21.6 billion.

AGRICULTURE - The White House budget proposed $46.54 billion in cuts to federal funding for the agriculture sector over the next 10 years, with the biggest cut in the form of a $38 billion bite out of farm supports, including new limits on subsidies for crop insurance premiums and caps for commodity payments.

FOREIGN OUTLAYS - The Trump administration's budget proposal would convert some of the United States' foreign military grants to loans, part of a larger effort to slash spending on diplomacy, aid and programs abroad by more than 29 percent.

ENERGY - Trump's White House would sell half of the nation's emergency oil stockpile and open the Alaska National Wildlife Refuge to drilling as part of a plan to balance the budget over the next 10 years and ramp up American energy output.

FINANCIAL REGULATION - Two Wall Street financial regulators, the Consumer Financial Protection Bureau and the Securities and Exchange Commission, would face cuts or major structural changes under Trump's budget proposal. The CFPB, created to protect borrowers from predatory lending, would undergo a "restructure" that would cut the federal deficit by $145 million, while the SEC, which polices securities markets, would have its reserve fund used to supplement its budget.

ASSUMPTIONS - Trump's promise to balance the federal budget in a decade rests on a sustained rise to 3 percent annual economic growth and a vague "feedback" effect that lowers the annual deficit by hundreds of billions of dollars. The projections are a leap of faith that many economists and the Federal Reserve regard as unlikely.

ECONOMY - A table detailing the main economic forecasts underlying the budget proposal

DEFICIT - A table detailing the deficit projections from the budget proposal

(Writing by Eric Walsh; Editing by Cynthia Osterman)