2024 election updates: Trump, Harris hit more battlegrounds

Trump and Zelenskyy are now meeting at Trump Tower.

"We're going to have a discussion and see what we can come up with, but a great honor to have you," Trump told reporters.

Trump and Zelenskyy then shook hands, with Zelenskyy thanking Trump for the meeting.

"The war in Ukraine has to be stopped and Putin can't win and Ukraine has to prevail. And I want to discuss with you in detail about our plan," Zelenskyy said.

After sources said Trump might not meet with the foreign leader while he is in the U.S., Trump told reporters on Thursday they will meet at 9:45 ET this morning at Trump Tower.

"It's a shame what's happening in Ukraine. So many deaths, so much destruction," Trump said. "It's a horrible thing. And one of the things that are very bothersome to me is the fact that Europe is paying only a small fraction of the money that the United States of America is paying, and we have an ocean between Russia and ourselves."

ABC News Senior Congressional Correspondent Rachel Scott asked Trump if he believed Ukraine should cede its own territory to Russia in order to end the war -- what Kamala Harris called "surrender."

"We'll see what happens," Trump said. "Let's get some peace. We need peace. We need to stop the death and destruction, don't you think? Wouldn't that be nice?"

The Secret Service informed Trump’s campaign it wouldn’t be able to accommodate his outdoor rally in Wisconsin on Saturday due to manpower issues, according to a source briefed on the situation.

The campaign wanted to have a rally at an airport hangar, but due to the Secret Service being stretched thin with the U.N. General Assembly in New York, it didn’t have the number of agents necessary to secure that site. A source said Secret Service personnel and equipment are being pushed to their limits to sustain the current operational tempo.

Trump’s detail is akin to those of President Joe Biden and Harris, with the exception of Defense Department assets on their details, and the agency wasn’t built to handle these increasing needs, according to a source familiar with the planning.

"Former President Donald Trump is receiving heightened levels of U.S. Secret Service protection and our top priority is mitigating risks to ensure his continued safety at all times,” Anthony Gugliemi, Secret Service chief of communications, said. “Out of concern for operational security, we cannot provide specific details about resources allocated for event security or communications between agency personnel and our protectees."

The Trump campaign hasn’t responded to ABC News’ request for comment.

ABC News' Luke Barr

Trump blasted Harris' record as he spoke about immigration at Trump Tower in New York, .

"Kamala Harris will be visiting the southern border that she has completely destroyed, from what I understand, tomorrow," Trump said. "Why would she go to the border now, playing right into the hand of her opponent? I mean, you take a look at this -- why would you do that? There can be no justification for what she’s done."

Trump is going through a lengthy list of his grievances with Harris and continued to demonize migrants.