Trump admin updates: US military is preparing for possible activation of National Guard in DC

Trump on Tuesday signed an executive order establishing a White House task force on the 2028 Summer Olympics, which are being held in Los Angeles. Trump said the order will mobilize various government agencies "to ensure the games are safe, seamless and historically successful."

"America is a nation of champions, and in July 2028, we'll show the world what America does best. And that's when we're winning like we have never won before," Trump said.

Members of the task force include Vice President JD Vance, Attorney General Pam Bondi, Homeland Security Secretary Kristi Noem, White House chief of staff Susie Wiles and other officials.

Also present for Tuesday's signing was Olympic gymnast Nastia Liukin, Paralympian swimmer Brad Snyder and chairman of the U.S. Olympic Committee Gene Sykes.

Trump thanked Sykes for changing the committee's policy to bar transgender women from being eligible to compete for the United States in the Olympic or Paralympic Games in women's categories.

"The United States will not let men steal trophies from women at the 2028 Olympics. So, we appreciate the fairness and everything else that you've shown," Trump said.

Michigan Gov. Gretchen Whitmer, a Democrat, met with President Donald Trump Tuesday at the White House to discuss the impacts his tariffs are having on Michigan's economy and changes made to Medicaid, a spokesperson for the governor confirmed to ABC News.

"Today, I went to the White House to meet with President Trump. I told him and his team about the impact tariffs are having on Michigan's economy, especially our auto industry, the harm Michigan will face due to changes in the Medicaid program, and ongoing recovery efforts following the ice storm in Northern Michigan this year," Whitmer said in a statement to ABC News.

During the meeting, Whitmer made clear the negative impact Trump's tariffs are having on Michigan, given that the state's economy is tied to the auto industry, and tariffs have a disproportionate impact on this industry.

Whitmer, a Democrat, has met with Trump multiple times this year about addressing the needs of the state of Michigan. Whitmer last met with Trump in April in Michigan during an event at Selfridge Air National Guard Base.

-ABC News' Hannah Demissie

Ever the developer-in-chief, Trump made a surprise appearance on the White House roof above the briefing room, apparently inspecting future construction.

The media, which had been pushed significantly down the driveway, attempted to figure out what was going on.

"Mr. President, what are you doing up there?"

"Just taking a little walk," he shouted back.

"What are you building?"

"It goes with the ballroom, which is on the other side," he said.

Pressed again by reporters Trump replied "something beautiful” while pantomiming with his hands.

Trump said it was "Just more ways to spend my money," adding "Just more ways to spend my money for the country."

"Anything I do is financed by me," he stressed.

The president was accompanied by a small group of aides and Secret Service. The group included architect Jim McCrery, who has been commissioned to add Trump's ballroom to the White House. The two men appeared engaged in intense conversation as they surveyed the grounds -- with lots of animated pointing.

"What are you trying to build?" one reporter shouted.

"Missiles," Trump responded, presumably joking. "Nuclear missiles," he repeated while making the gesture of a rocket launching.

-ABC News’ Mary Bruce and Lalee Ibssa

When asked how exactly the U.S. is going to enforce the terms of the foreign trade deals to make sure these promised investments actually happen, President Donald Trump brushed off concern but noted that if they don't make the investments, their tariff rate will increase.

Well, then they pay tariffs for 35%," Trump said on CNBC Tuesday when asked what happens if the European Union investments don't happen.

Trump also insisted that the investments are not loans.

When asked about the details of what that $600 billion investment will go to, Trump said it will go to "anything" he wants.

"The details are $600 billion to invest in anything I want, anything I can do, anything I want, whether and the purpose was, they've been, you know, ripping us for so many years that it's time that they pay up, and they have to pay up," Trump said.

-ABC News' Michelle Stoddart