LONDON — President Donald Trump said he is prepared to talk to Iranian President Hassan Rouhani, but added “there's always a chance” the U.S. would need to take military action.

He made the comments during his state visit to the U.K. in an interview with British television presenter Piers Morgan on Tuesday evening.

“I’d much rather talk,” said Trump, sitting in the Churchill War Rooms, the underground complex where then-Prime Minister Winston Churchill directed the World War II effort, now a museum.

But Trump stressed that there were limits to what he would be willing to accept from the Islamic Republic.

“The only thing is, we can’t let them have nuclear weapons. Don’t forget that I’m the one that gets trained and has to study that. I see the damage done, I see the horrible damage done,” he said. “I don’t want them to have nuclear weapons.”

Iranians in Tehran burn a mask of President Trump during a protest marking the annual al-Quds Day on the last Friday of the holy month of Ramadan on May 31. Meghdad Madali/Tasnim News Agency / Reuters

The comments mirrored those of Secretary of State Mike Pompeo, who said on Sunday that the Trump administration was ready for unconditional talks with Iran.

Trump’s state visit in the U.K. continues Wednesday, when he will pay his respects to American service members and allies who turned the tide in the war against Nazi Germany.

Together with Queen Elizabeth II and Prime Minister Theresa May, Trump will visit the naval base at Portsmouth, around 75 miles southwest of London, which served as a key launch pad for the forces that landed on Normandy. It will be the first of two events commemorating the 75th anniversary of D-Day that Trump will attend this week.

Is the NHS on the table in a post-Brexit trade deal?



The president backflipped and told @piersmorgan he no longer considers it a part of trade. pic.twitter.com/AeNQ30UVBx — Good Morning Britain (@GMB) June 5, 2019

During the wide-ranging interview with Morgan, Trump seemed to walk back several comments he made prior to, and during, the state visit.

He said in a press conference earlier on Tuesday that Britain’s publicly funded National Health System, known as the NHS, would be on the table in a future trade deal. The comments echoed remarks that American Ambassador to the U.K. Woody Johnson made in an interview on Sunday.

However, in the discussion with Morgan, Trump said that the NHS would not be “on the table.”

“That’s something that I would not consider part of trade,” he said.

It is a particularly sensitive topic in the U.K., where health care is generally free at the point of use and funded through taxation. As soon as Trump made the comments, several candidates for the leadership of the ruling Conservative Party, including Health Secretary Matt Hancock, said that the NHS would not be part of any trade deal.

Did Donald Trump really call the Duchess of Sussex 'nasty'?



He clarifies his comment and says 'I think she's doing very well'.



He adds Prince Harry was 'a terrific guy' and 'couldn't have been nicer'. pic.twitter.com/ARwcyheeiv — Good Morning Britain (@GMB) June 5, 2019

Trump also attempted once again to clarify earlier remarks about the Duchess of Sussex, the former Meghan Markle, on Saturday. He seemed to suggest in an interview with The Sun newspaper that she was “nasty” for comments she made about him during the 2016 presidential campaign.

“I think she’s very nice. Honestly, I don’t know her,” he told Morgan. “It’s not good for me to be nasty to her and I wasn’t. In fact, I think she’s doing very well.”

He said the issue didn’t come up when he spoke with Markle's husband, Prince Harry, who "couldn't have been nicer."

On Wednesday’s engagement with the queen in Portsmouth, Trump will read an excerpt from the prayer President Franklin D. Roosevelt delivered on the evening of June 6, 1944, when he spoke to the American people for the first time about the operation in Normandy.

An anti-Trump protester in London on Tuesday. SOPA Images / Getty Images

When asked if he would have liked to have been able to serve in Vietnam, Trump said that he “was never a fan of that war. I thought it was a terrible war. It was very far away.”

However, he stressed that he is now making up for his lack of service with his support for the military.

“I think I’m making up for it rapidly because we’re building our military at a level that’s never been seen before,” he said.

Trump defended gun ownership in the U.S., saying that “the people that obey the laws, if there was a law passed, those people are sitting ducks.”

He said that many Americans have semi-automatic assault weapons, specifically the AR-15 that has been used in many of American’s worst mass shootings, for entertainment.

“For some people it’s entertainment. They go out and they shoot and they go to ranges, and they have a tremendous amount of fun,” he said.

His trip to the U.K. will end Wednesday evening, when he will travel to Ireland. There, he will spend two nights at his golf club in Doonbeg and will meet Irish Prime Minister Leo Varadkar.