President Donald Trump amended two executive orders on Sunday to exclude low-value shipments from the tariffs that are set to go into effect on imports from Canada and Mexico on Tuesday.

The move could be a sign that the White House is serious about moving forward with the tariffs, which were originally paused for 30 days so the countries could negotiate with the White House.

The change impacts two executive orders that aimed to stem the flow of illicit drugs into the United States. It now exempts imports valued at less than $800 from Canada and Mexico -- until the infrastructure is in place to start taxing those goods.

The amendments say that Commerce Secretary Howard Lutnick can start applying tariffs to those imports once the system is in place.

-ABC News' Michelle Stoddart and Elizabeth Schulze

There are real concerns within the intelligence community that foreign adversaries -- including Russia and China -- could target the growing ranks of recently fired federal employees for recruitment.

Agency officials are discussing this and warning colleagues and staff, sources tell ABC News.

“It's not difficult for a foreign spy service to find a target for recruitment. They just simply have to go online and look at the postings of people who've recently been fired, who are angry and who are in need of money,” said John Cohen, former Department of Homeland Security acting undersecretary for intelligence and an ABC News contributor.

“These large-scale layoffs and firing potentially could cause a counter-intelligence and security nightmare.”

Cohen added that if these types of large-scale layoffs were happening in Russia or China, the U.S. would also be working “aggressively” to identify individuals to recruit as intelligence assets.

The White House National Security Council did not respond to multiple requests for comment.

CNN reported earlier that foreign adversaries have recently directed their intelligence services to ramp up recruiting of fired federal employees who worked in national security, citing unnamed sources and a document produced by the Naval Criminal Investigative Service. That document, according to CNN, said foreign intelligence officers were being directed to look for potential sources on LinkedIn, TikTok, RedNote and Reddit.

-ABC News’ Josh Margolin, Pete Madden, Kristen Red-Horse and Selina Wang

In a new Fox News op-ed on Sunday, Health and Human Services Secretary Robert F. Kennedy Jr. said that the measles outbreak in Texas is "a call to action for all of us."

"As the Secretary of the U.S. Department of Health and Human Services, I am deeply concerned about the recent measles outbreak," Kennedy wrote in the op-ed.

Kennedy said that 146 confirmed cases have been found in Texas since late January and that he has directed the Centers for Disease Control and Prevention and Administration for Strategic Preparedness and Response to support Texas health officials. He added that he spoke to Texas Gov. Greg Abbott and parents who lost children to measles "to offer consolation."

Kennedy, who has a history of vaccine skepticism, stopped short of calling for vaccinations in the piece, but he did say that government should "make vaccines readily accessible for all those who want them" and advised parents to talk to their health care providers about the MMR vaccine.

"All parents should consult with their healthcare providers to understand their options to get the MMR vaccine. The decision to vaccinate is a personal one. Vaccines not only protect individual children from measles, but also contribute to community immunity, protecting those who are unable to be vaccinated due to medical reasons," Kennedy said in the op-ed.
-ABC News’ Michelle Stoddart

Trump will undergo a physical exam "next month," his physician said in a statement.

The routine annual examination will take place at Walter Reed National Military Medical Center, said Dr. Sean Barbabella, Trump's newly appointed physician.

"The date of his physical exam will be released publicly in the next few weeks," Barbabella said.

The White House statement comes several days after reporters raised questions about a bruise they observed on the back of Trump's right hand during his White House meeting with French President Emmanuel Macron on Monday.

White House press secretary Karoline Leavitt said in a statement that the bruise came from shaking hands.

"President Trump is a man of the people and he meets more Americans and shakes their hands on a daily basis than any other President in history. His commitment is unwavering and he proves that every single day," Leavitt said.