Trump has complained bitterly about stonewalling by Democrats, who withheld support early on for many of the president's Cabinet-level nominees. Half of Trump's Cabinet picks were approved by slim majorities. Education Secretary Betsy Devos, for example, required a tie-breaking vote from Vice President Mike Pence.
But Democrats in Congress say they can't stall nominations that haven't been made.
As of Monday, the White House had yet to put forward the names of candidates for 204 of the 665 key positions that require Senate confirmation, according to the Partnership for Public Service, a nonpartisan group that advises incoming administrations.
The longest list of empty desks waiting to be filled is at the State Department, where more than 40 top jobs are vacant. Dozens of ambassadors appointed by the Obama administration were fired by Trump on Inauguration Day and have yet to be replaced.
The unfilled jobs also include key positions throughout the executive branch charged with rooting out waste, fraud and abuse. Despite Trump's campaign vows to "drain the swamp," his administration has been slow to hire agency watchdogs, known as inspectors general, tasked with reviewing the way the government conducts its business and spends taxpayers' money.