After days of opposition and hours before the federal government was going to shut down, Trump signed a $2.3 trillion bill into law Sunday night to avert a government shutdown and extend $900 billion in coronavirus pandemic relief -- but millions of American will be impacted by his delay.

Trump’s Sunday night signature came after two critical unemployment programs lapsed over the weekend, leaving roughly 14 million Americans who have relied on the income without a week of benefits during the holiday season. While the current bill shells out $600 direct payments for most Americans, Trump is breaking from his party by continuing his push to bring that amount to $2,000.

In a Sunday night statement announcing he had signed the bill, Trump -- who has sat on the sidelines of negotiations for months -- also called on Congress to make more revisions to cut down excess spending, saying "wasteful items need to be removed" from the bill and that he would send back a “redlined” version.

The move is forcing Senate Republicans, many who did not support more direct payments, to say whether they stand with Trump on increasing payments and revisiting the bill’s language or by their previous positions.

House Speaker Nancy Pelosi on Monday is bringing a vote on a stand-alone bill to increase economic impact payments to $2,000 to the House floor, and while it’s expected to pass the House, it’s unclear whether Senate Majority Leader Mitch McConnell will take up the measure in the Senate.

The president has no public events on his schedule as he continues his holiday from Mar-a-Lago, and threatens, via Twitter, a challenge to the counting of the Electoral College vote in Congress on Jan. 6.

Biden, meanwhile, is pressing forward with his transition with less than a month until his inauguration. The president-elect is slated to meet with members of his national security and foreign policy agency review teams on Monday and deliver afternoon remarks on their "findings and the key challenges his administration will inherit" from Wilmington, Delaware.

Biden took aim at Trump in remarks following a briefing on national security and foreign policy, slamming the current administration for failing to fully cooperate with his agency review teams during the transition -- which Biden argued could leave the country vulnerable.

While commending his own agency review teams for their hard work amid a transition that was already made more challenging by COVID-19, Biden pointedly called out Department of Defense and White House Office of Budget and Management political appointees for, he said, not cooperating for a smooth transition.

"And the truth is many of the agencies that are critical to our security have incurred enormous damage. Many of them have been hollowed out in personnel, capacity and in morale," Biden added.

Later in his remarks, Biden stressed the need for cooperation during the transition, noting that it is a matter of national security to ensure there are no gaps that adversaries can seek to exploit when he takes office.

"We need full visibility into the budget planning under way at the Defense Department and other agencies in order to avoid any window of confusion or catch-up that our adversaries may try to exploit," Biden said. "Right now, we just aren't getting all the information that we need from the outgoing administration in key national security areas. It's nothing short, in my view, of irresponsibility."

Biden said other "Day One" challenges discussed in the briefing will draw on the skill sets of the Department of Homeland Security and the Federal Emergency Management Agency as they aim to "clean up the humanitarian disaster that the Trump administration has systematically created on our Southern border."

"We will institute humane and orderly responses. That means rebuilding the capacity we need to safely and quickly process asylum seekers, without creating near-term crises in the midst of this deadly pandemic," Biden said.

As he exited the stage at the Queen Theater in Wilmington, Delaware, Biden was asked if he supports the measure for $2,000 direct payments to Americans for COVID-19 relief, which the House will soon vote on. He responded with one word: "Yes."

-ABC News' Molly Nagle, Sarah Kolinovsky and Beatrice Peterson