Updated at 7:04 p.m. ET

President-elect Joe Biden is complaining that the outgoing Trump administration has thrown up some "roadblocks" as he and advisers prepare to take the White House.

In prepared remarks Monday in Wilmington, Del., Biden said that he and his team have been frustrated by what he called a lack of cooperation, especially at the Defense Department and with the Office of Management and Budget.

"All of it makes it harder for our government to protect the American people," Biden said, calling the alleged failures of cooperation from political leaders at the agencies "nothing short of irresponsibility."

Biden's comments followed an earlier flap about meetings between current Pentagon leaders and those in the incoming camp; current Defense Department officials had downplayed accounts about delays or cancellations, but Biden made it clear on Monday he remains unhappy about the state of that relationship.

Biden said he and Vice President-elect Kamala Harris need a complete picture of the workings of government because of the magnitude of the challenges they'll confront on taking office next month.

"We need to make sure nothing is lost in the handoff between administrations," he said. "We need full visibility."

In a statement, acting Defense Secretary Christopher Miller said his department has conducted 164 interviews and provided over 5,000 pages of documents — "far more than initially requested by Biden's transition team."

"Our DoD political and career officials have been working with the utmost professionalism to support transition activities in a compressed time schedule and they will continue to do so in a transparent and collegial manner that upholds the finest traditions of the Department," Miller said.

The president-elect said not all agencies have been problematic and some of the interactions his team is having are "exemplary." Broadly, however, he described a national security and foreign policy institution in Washington that includes many entities Biden said were "hollowed out," short on "personnel, capacity and morale" and in which "policy processes have atrophied or been sidelined."

President Trump dismissed his most recent Senate-confirmed defense secretary, Mark Esper, and replaced him with Miller. The White House also replaced a number of other Pentagon leaders with interim replacements for the final weeks until Inauguration Day.

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