Trump admin live updates: Gov. says 'no need' after Trump directs troops to Portland

Lindsey Halligan was officially sworn in as the interim U.S. Attorney for the Eastern District of Virginia, Attorney General Pam Bondi announced on social media Monday.

Halligan, who most recently worked in the White House staff secretary's office, represented President Trump for a time during the classified documents investigation.

Trump said Saturday that he would appoint his former attorney to lead the key federal prosecutor's office after the previous head, Erik Siebert, resigned his position amid pressure from Trump administration officials to bring a criminal case against New York Attorney General Letitia James.

President Trump made an announcement from the Oval Office on autism, flanked by Health and Human Services Secretary Robert F. Kennedy Jr. and Centers for Medicare & Medicaid Services Administrator Mehmet Oz.

"Today, we're delighted to be joined by America's top medical and public health professionals as we announced historic steps to confront the crisis of autism. Horrible, horrible crisis," Trump said.

He and his top officials stated the use of Tylenol during pregnancy may be linked to an increased risk of autism.

Trump said the Food and Drug Administration will begin notifying physicians immediately that it is "strongly recommending that women limit Tylenol use during pregnancy unless medically necessary."

"They are strongly recommending that women limit Tylenol use during pregnancy unless medically necessary," Trump said. "That's, for instance, in cases of extremely high fever."

Studies on this question have not shown a direct cause and effect. Some studies point to a possible link, but major medical groups have evaluated the evidence and continue to recommend acetaminophen as the safest painkiller during pregnancy.

-Mary Kekatos, Cheyenne Haslett and Sony Salzman

White House press secretary Karoline Leavitt said that President Donald Trump will sign an executive order designating Antifa as a terror organization as early as Monday afternoon.

"Well, Antifa is going to be designated a domestic terrorist organization. The president intends to sign that executive order very soon, as soon as it's drafted, as soon as today -- later this afternoon," Leavitt told reporters during Monday's briefing. Though currently, federal law does not allow for U.S. organizations to be labeled "terrorist" groups.

Leavitt also reiterated Trump's pledge to go after left-leaning organizations he claims contribute to political violence.

"Enough is enough. As President Trump has promised, he will directly address the dark sources funding and supporting this domestic terrorism to finally restore order in our country. The American people can expect further very strong action on this very soon," Leavitt told reporters at Monday's briefing, after listing several examples of political violence against Republican figures while not mentioning recent attacks against Democrats.

White House press secretary Karoline Leavitt on Monday insisted President Donald Trump is seeking "accountability" when asked whether Trump's public pressure on Attorney General Pam Bondi to prosecute his political rivals constitutes "retribution."

Leavitt claimed New York Attorney General Letitia James is a "corrupt politician" who "abused her oath of office," despite federal prosecutors coming up empty after five months of extensive investigations into James.

When pressed by ABC News on why the president wouldn't accept the conclusion of his Justice Department not to bring charges against James, Leavitt said he has a right to "express how he feels" about people who "tried to ruin his life and his business."

-ABC News' Selina Wang, Michelle Stoddart and Lalee Ibssa