Making good on a promise to slash government, President-elect Trump has asked his incoming team to pursue spending and staffing cuts.

Insiders said that the spending reductions in some departments could go as high as 10 percent and staff cuts to 20 percent, numbers that would rock Washington if he follows through.

At least two so-called "landing teams" in Cabinet agencies have relayed the call for cuts as part of their marching orders to shrink the flab in government.

The cuts would target discretionary spending, not mandated programs such as Medicare or Social Security, the sources said.

The spending reductions are expected to be used to help pay for Trump's plan to boost the Pentagon's budget, tax cuts and some pet projects, potentially including the anti-immigration wall on the nation's southern border.

The teams also are looking at staffing cuts over four years through attrition, a hiring freeze and reorganization.

The plan is winning cheers in conservative, anti-tax and anti-spending corners in Washington that have long sought massive cuts in the bureaucracy.

Presidents rarely cut spending, choosing freezes instead. In the meantime, federal spending has reached historic levels. Trump has picked a budget hawk, Rep. Mick Mulvaney, to head the Office of Management and Budget, a clear sign that spending cuts are a top priority.

Still, Trump is likely to face a wall of opposition from Democrats and federal unions who consider much of the federal workforce on their side.

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com