Donald Trump may be in for some awkward meetings when he visits the U.K. this year
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When President Donald Trump arrives for his official State Visit to the U.K. later this year, he will be in for some awkward meetings.

Prince Charles is not going to shy away from talking about issues that mean the most to him — like climate change and religious tolerance — when he meets the president, a source tells PEOPLE.

And then there are the eyebrow-raising comments Trump’s made about Princess Kate. In 2012, the reality star tweeted about the notorious topless photos of Kate sunbathing in a private home, saying “who wouldn’t take Kate’s picture and make lots of money if she does the nude sunbathing thing.” At the time, the palace slammed the publication of the photos, saying Kate was “deeply saddened.” The tweet remains on the President’s official Twitter account.

Years earlier, just weeks after Princess Diana‘s tragic 1997 death, Trump made smutty comments about the beloved royal during an appearance on Howard Stern’s radio show that he thought he could have “nailed” the princess after her divorce.

“Why do people think it’s egotistical of you to say you could’ve gotten with Lady Di?” Stern asked Trump in the interview. “You could’ve gotten her, right? You could’ve nailed her.”

Trump replied: “I think I could have.”

In a separate appearance on Stern’s show in 2000, Trump said he would have slept with Diana “without hesitation,” adding that she was “crazy, but these are minor details.”

Prince Of Wales And Duchess Of Cornwall US Visit - Day 1
Credit: Chris Jackson/Getty

Trump’s comments about Diana were used in ads by Hillary Clinton‘s presidential campaign as an example of the troubling way he has spoken about women in the past.

Reports surfaced on Sunday that Trump’s team wants to side-step any meeting with Charles, favoring schmoozing with Prince William, Kate and Prince Harry.

But each potential meeting comes with pitfalls. At root of the issue between Trump and Charles is the former’s stance on climate change, which he once called a “concept created by the Chinese to make the [U.S.] non-competitive,” while Charles is a passionate campaigner on the issue.

According to The Sunday Times, a White House source said that the President doesn’t want to be talked down to by Charles about the issue.

“He won’t put up with being lectured by anyone, even a member of the royal family,” the source said. “Frankly, they should think twice about putting him and Prince Charles in the same room together.”

The prince has made no secret of his belief that climate change is one of the key issues of our time. A royal source tells PEOPLE that Charles will not be stopped from raising the issue with Trump, but he will do so when it’s “entirely appropriate to the situation.

Andrew Matthews/PA Wire/ABACAPRESS
Credit: Andrew Matthews/PA Wire/ABACAPRESS

“It’s not the first time he has had a meeting with a public figure who may not entirely be ideologically aligned with him. But it doesn’t mean that those meetings can’t happen.”

The source adds, “He won’t be lecturing anyone. The prince is very relaxed about meeting the President, and while those conversations are private, the topic is likely to be raised.”

“But it will be raised in a manner appropriate to the circumstances. It will not create an embarrassing moment.”

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The visit was announced on Friday and has since come under fire in the U.K, where a petition of more than one million people has called for it to be canceled to avoid “embarrassing” the queen.

As heir to the throne, the prince, along with his wife Camilla, Duchess of Cornwall, will take a prominent place in the visit. He normally meets the visiting head of state and brings them to Horse Guards Parade where there is the formal welcome by his mother the queen. Then, a lunch at Buckingham Palace typically follows.

American state visits have not always featured a tea or a private meeting with the Prince of Wales. The state visits tend to be shorter with American presidents. But Charles did, for example, have a tea with the visiting President of China, Xi Jingping.

Catherine, Duchess of Cambridge
Credit: Dominic Lipinski/WPA Pool /Getty

William and Kate, who are planning on basing themselves back in London as they undertake more royal roles, may be involved too. They have increasingly taken part in incoming state visits, most famously when they helped the queen host the Chinese president Xi Jinping at a Buckingham Palace state banquet.

It is the U.K. government who decides on the timing and whether a visit goes ahead – and advises the palace on the invitation. A formal announcement on the date will be made in due course, though it could happen as early as June.

Neither Buckingham Palace nor Clarence House, where the Prince of Wales has his office, could comment on the reports. William and Kate’s spokesman at Kensington Palace also had no comment.