Trump says 3rd term isn't a joke, despite term limit

Dr. Peter Marks, the Food and Drug Administration's top vaccine official who played a crucial role in the development of COVID-19 vaccines during the pandemic, has resigned, with one source telling ABC News that he was pushed out of his position by Health and Human Services Secretary Robert F. Kennedy Jr.

Marks, who has served as the FDA's vaccine chief since 2016, resigned in a letter sent to acting FDA Commissioner Sara Brenner. In it, he alleged Kennedy is not interested in "truth and transparency" but rather in "subservient confirmation of his misinformation and lies."

Marks called the measles outbreak a reminder of "what happens when confidence in well-established science underlying public health and well-being is undermined."

The measles vaccine "very simply does not cause autism," Marks wrote.

"My hope is that during the coming years, the unprecedented assault on scientific truth that has adversely impacted public health in our nation comes to an end so that the citizens of our country can fully benefit from the breadth of advances in medical science," Marks wrote.

A source familiar with the situation told ABC News that Marks was given the choice by a department official either to resign or be fired.

Asked for comment, an HHS official said, "If Peter Marks does not want to get behind restoring science to its golden standard and promoting radical transparency, then he has no place at FDA under the strong leadership of Secretary Kennedy."

Marks has been the FDA's vaccine chief since 2016. His resignation will end nearly a decade of monitoring vaccine development, evaluating their safety and recommending how the public should use them -- and perhaps doing the role during one of the most critical eras in public health.

His role became incredibly high profile during the pandemic, when Marks oversaw the approval of the first coronavirus vaccines -- and oversaw the intensely watched process through the many developments.

-ABC News' Cheyenne Haslett, Will McDuffie and Youri Benadjaoud

President Donald Trump will host El Salvador's president, Nayib Bukele, in Washington in April, the El Salvador Vice President's Office told ABC News.

An exact date of the meeting has not been decided.

El Salvador is home to the migrant prison Homeland Security Secretary Kristi Noem toured this week. While some of alleged gang members sent to El Salvador have had criminal records, a top ICE official told a federal judge that many did not.

Editors Note: This blog post has been updated

-ABC News' Aicha Elhammar

A federal appeals court overruled Friday a lower court's order that blocked Musk and the Department of Government Efficiency from dismantling the U.S. Agency for International Development.

A panel of three judges on the U.S. Court of Appeals for the 4th Circuit stayed a lower court's ruling, finding that the Trump administration is likely to prove that the DOGE's effort to dismantle USAID did not violate the Constitution.

"While defendants' role and actions related to USAID are not conventional, unconventional does not necessarily equal unconstitutional," Judge A. Marvin Quattlebaum Jr. wrote in a concurring opinion.

-ABC News' Peter Charalambous

The Trump administration filed suit Thursday against the largest federal union that represents government employees in what it describes as an "affirmative" effort to invalidate collective bargaining contracts as President Donald Trump hopes to bolster his legal standing in laying off thousands of federal workers.

The lawsuit filed by the Justice Department on behalf of eight other government agencies argues that collective bargaining agreements with affiliates of the American Federation of Government Employees hinders the agencies' abilities to perform critical national security work.

It also comes as the administration has been frustrated by multiple court rulings that have reversed or halted its efforts to lay off broad swathes of government workers.

-ABC News' Alexander Mallin