Biden will move to release more doses of the COVID-19 vaccine when he takes office, a departure from the country's current procedure of withholding 50% of the supply to ensure second doses of the two-shot vaccine are available, a transition official said Friday.

“He supports releasing available doses immediately, and believes the government should stop holding back vaccine supply so we can get more shots in Americans' arms now. He will share additional details next week on how his Administration will begin releasing available doses when he assumes office on January 20th,” Biden spokesperson TJ Ducklo said in a statement.

A transition official told ABC News they have faith manufacturers can produce enough vaccines to ensure people can get their second doses in a timely manner, while also getting more people their first doses.

The official also noted the Biden administration has long pledged to use the Defense Production Act as needed to help produce materials to ensure supply.

-ABC News' Molly Nagle and Anne Flaherty

In a short statement, Col. Dave Butler, spokesperson for Chairman of the Joint Chiefs of Staff, confirmed the nation's top Gen. Mark Milley and House Speaker Nancy Pelosi spoke on the phone.

"Speaker Pelosi initiated a call with the chairman. He answered her questions regarding the process of nuclear command authority," Butler said.

Pelosi told her Democratic colleagues in a letter earlier Friday she reached out to discuss "available precautions" for preventing Trump "an unstable president" from accessing the nuclear launch codes or initiating military hostilities before he is out of office in 12 days.

-ABC News' Matt Seyler

A Twitter spokesperson said in a statement Friday: “In line with our statement yesterday, any future violations of the Twitter Rules, including our Civic Integrity or Violent Threats policies, will result in permanent suspension of the @realDonaldTrump account.”

The social media platform on Wednesday removed a video of Trump telling Capitol Hill rioters "we love you" and to "go home," requested the removal of three of Trump's tweets and slapped a 12-hour lock on Trump's account by Wednesday night.

"If the Tweets are not removed, the account will remain locked," the company added in a Tweet on its verified safety account at the time.

A Twitter spokesperson told ABC News on Thursday morning that Trump’s tweets were deleted.

-ABC News' Ben Gittleson

House Speaker Nancy Pelosi a letter to her Democratic colleagues said she reached out to the Chairman of the Joint Chiefs of Staff Mark Milley Friday morning to discuss "available precautions" for preventing Trump -- "an unstable president" -- from accessing the nuclear launch codes or initiating military hostilities before he is out of office in 12 days. She doesn't elaborate further on their discussion.

"This morning, I spoke to the Chairman of the Joint Chiefs of Staff Mark Milley to discuss available precautions for preventing an unstable president from initiating military hostilities or accessing the launch codes and ordering a nuclear strike. The situation of this unhinged President could not be more dangerous, and we must do everything that we can to protect the American people from his unbalanced assault on our country and our democracy," she said in the letter.

Pelosi said she is also still waiting to hear back from Vice President Mike Pence as to whether or not he intends to invoke the 25th Amendment ahead of House Democrats holding a call on their options on removing Trump from office at noon.

"If the President does not leave office imminently and willingly, the Congress will proceed with our action," she wrote.

-ABC News' Mariam Khan

House Speaker Nancy Pelosi, in a new letter to Democrats on Saturday, asked members to prepare to return to Washington this week -- another signal that the House could take up and pass the impeachment article to the Senate after it is formally introduced on Monday.

Pelosi thanked fellow Democratic representatives for speaking with her on a conference call Friday and said she was taking their considerations into account. She did not specifically mention voting on impeachment in the letter, though.

"Since that call, I have received scores of communications from Members expressing your views about how we go forward and regarding a strong presence of our Caucus in the Capitol," she wrote. "Over the last few days, I have discussed your views with Constitutional lawyers, both inside and outside the Congress, to consider the parliamentary and constitutional options available to us."

"From what I have heard from Members, and from the deluge that I have received from the public, it is clear that, once again, the Times Have Found Us to save our democracy," Pelosi added in the letter. "We will be proceeding with meetings with Members and Constitutional experts and others. I continue to welcome your comments. I urge you to be prepared to return to Washington this week."

While Democrats are hopeful Republicans will back their effort, none have come out and said they would back the charge as drafted.

Pelosi said at a press conference on Thursday, "If the Vice President and Cabinet do not act [on the 25th Amendment], the Congress may be prepared to move forward with impeachment."

Some Democrats planned to connect with Republican colleagues this weekend to gauge their support and encourage them to back the effort.

-ABC News' Benjamin Siegel