U.S. President Donald Trump used a joint press conference with Italian Prime Minister Giuseppe Conte as an opportunity to broach Italy's trade surplus with the United States.

"Italy has a $31 billion surplus with the United States, meaning we have a $31 billion trade deficit with Italy, and we discussed that," Trump said. "We'll work something out."

Trade and defense spending were central themes of the press conference, as Trump touted meetings with European Commission President Jean-Claude Juncker and NATO member nations during the visit.

"Jean-Claude and I had a fantastic meeting last week," Trump said. "We were having a hard time and then I did mention tariffs on cars, and we got along very well … I think they're going to treat us very fairly, and we're going to treat them fairly."

Turning his attention to Iran, Trump also said he would have "no preconditions" to a meeting with Iran because there's "nothing wrong with meeting" when it concerns matters of global security.

"I would certainly meet with Iran if they wanted to meet," he said. "I don't know that they're ready yet. They're having a hard time right now."

Trump also used the press conference to double down on his threat to shut down the government if Congress does not produce what he feels is a satisfactory immigration package, though he said he is willing to negotiate.

"I'll always leave room for negotiation, but this has been many years," Trump said in reference to U.S. immigration policy reform, adding that he has "no red line."