By LIBBY CATHEY, ADIA ROBINSON LAURAN KING, CATHERINE THORBECKE, LAUREN LANTRY and KIARA BRANTLEY, ABC News

(WASHINGTON) — President Donald Trump is slated to hand over control of the White House to President-elect Joe Biden in 54 days.

Here is how the transition is unfolding. All times Eastern:

Nov 27, 12:24 pm
Without evidence, Trump disputes Biden’s popular vote lead

Despite telling reporters Thursday that he would leave the White House if Biden is inaugurated, while still not conceding, Trump continued on Friday to baselessly cast doubt on the president-elect’s record-breaking popular vote lead.

In a tweet Friday morning, Trump wrote, “Biden can only enter the White House as President if he can prove that his ridiculous “80,000,000 votes” were not fraudulently or illegally obtained” and went on to allege — without citing any proof — that Biden “got a big unsolvable problem!”

As reported previously by ABC News, the Trump campaign and its allies have lost at least 30 cases brought in the effort to overturn the results of the election, according to an ABC News count.

Biden won the Electoral College by the same margin as Trump did in 2016 and leads in the popular vote by over 80 million votes.

-ABC News’ Alisa Wiersema

Nov 27, 11:49 am
Progressives worry about lobbying, corporate ties in Biden administration

Several leading candidates for the roles in president-elect Joe Biden’s administration have (come under scrutiny)[] for their work in corporate America or lobbying history.

Michele Flournoy, a leading candidate for the head of the Department of Defense after serving in senior posts at the Pentagon during the Clinton and Obama administrations, has faced criticism from progressive and left-leaning activists for her ties to defense contractors and a strategic advisory firm that has faced questions about its clients.

Several other Cabinet selections and initial White House hires for the Biden administration, along with members of his transition efforts, are under the microscope as well, showing an early struggle between the activist and established wings of the Democratic Party, which collaborated to elect Biden and deny President Donald Trump a second term.

-ABC News’ Benjamin Siegel and Soo Rin Kim

Copyright © 2020, ABC Audio. All rights reserved.