Prince William and his wife Kate Middleton are coming to the U.S. for the first time in eight years, but it’s unlikely that they’ll be reunited with Prince Harry and Meghan Markle.

A source close to the Prince and Princess of Wales told ETOnline on Monday that the couple has "no plans" to see the Duke and Duchess of Sussex during their visit.

William and Middleton, both 40, are heading to Boston, Massachusetts, for the second annual Earthshot Prize Awards ceremony. As for the Sussexes, it’s likely they’ll still be in California before they head to the same region the following week when they visit New York. The Prince and Princess of Wales will travel to Boston on Wednesday for three days of public engagements.

Reps for the Prince and Princess of Wales as well as the Duke and Duchess of Sussex didn’t immediately respond to Fox News Digital’s request for comment.

PRINCE WILLIAM PLANS FIRST US VISIT IN 8 YEARS WITH KATE MIDDLETON FOR GLOBAL ENVIRONMENTAL AWARDS CEREMONY

The Fab Four at Queen Elizabeth's funeral

It is believed the Prince and Princess of Wales and the Duke and Duchess of Sussex last saw each other at Queen Elizabeth II's funeral in September of this year. (Darren Fletcher - WPA Pool/Getty Images)

According to the insider, William and Middleton are "excited" for their first international trip since taking on their new titles as Prince and Princess of Wales. The source noted that while the couple "appreciates the history associated to their titles, they understandably want to look to the future and pave their own paths."

During their trip, the pair hope to "meet the local community" and learn how climate change is being addressed in the state. The trip will end with the ceremony at the MGM Music Hall in hopes of raising awareness of the innovative work that’s being done to protect the environment.

Earthshot offers 1 million pounds ($1.2 million) in prize money to the winners of five separate categories: nature protection, clean air, ocean revival, waste elimination and climate change. The winners and all 15 finalists also receive help in expanding their projects to meet global demand.

In September of this year, Vanity Fair’s royal correspondent Katie Nicholl alleged that the rift between the brothers has deepened over the years.

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Prince William, Kate Middleton Meghan Markle Prince Harry looking serious

Vanity Fair's royal correspondent Katie Nicholl claimed that the rift between Prince William and his younger brother Prince Harry has deepened over the years. (Emilio Morenatti - WPA Pool/Getty Images)

"William simply can’t forgive [Harry], not just for his behavior and what he’s done and how he’s done it, but look at how much now rests on William," Nicholl explained on "Dan Wooton Tonight."

"He always thought Harry would be his wingman," she said. "Now he’s doing it on his own. Thank goodness he’s got Kate by his side."

In her book "The New Royals," Nicholl pointed out that "there were raised eyebrows at the palace" after Harry spoke of his meeting with Queen Elizabeth II on the "Today" show. During his appearance in April of this year, the 38-year-old said he wanted to ensure that his grandmother was "protected" and had "the right people around her."

"It wasn’t clear whether Harry was referring to his father and William or the aides who were closest to the queen – such as her private secretary, Sir Edward Young, her personal adviser and in-house dress designer, Angela Kelly, and trusted courtier Paul Whybrew," Nicholl wrote. "It seemed Harry’s drive to win back some of the trust that had been shattered post-Oprah was dashed. There was also still the matter of what Harry plans to disclose in his forthcoming memoir."

'FAB FOUR' ROYAL REUNION IN US? WILLIAM, KATE TO BE IN BOSTON DAYS BEFORE HARRY, MEGHAN TO BE HONORED IN NY

Prince Harry, Meghan Markle Oprah

Prince Harry and Meghan Markle gave their bombshell interview to Oprah Winfrey in March 2021. Harry is releasing his memoir ‘Spare’ next year. (Harpo Productions)

"For [King] Charles and William, the situation with the Sussexes hasn’t just been hurtful and upsetting on a personal level," she claimed. "There have been real repercussions, particularly for William, whose young family has been thrust into the spotlight prematurely. He always expected Harry would be his wingman; there was a long-term plan in place for the brothers to work together and support one another."

The Duke and Duchess of Sussex stepped back as senior royals in 2020 over what they described as the British media’s intrusions and racist attitudes toward the former "Suits" star, 41. The couple’s decision was dubbed "Megxit" by the press.

"After Harry announced their departure, William summoned aides to address the future, in what has been referred to by some in William’s circle as the ‘Anmer Summit,’" Nicholl claimed. "But William and Kate also felt a sense of relief that ‘the drama was gone’ when Harry and Meghan left, as a source told me. To this day, William still cannot forgive his brother."

In the wake of quitting royal duties, the Duke and Duchess of Sussex gave an explosive TV interview to Oprah Winfrey, in which the couple described painful comments about how dark their son’s skin might be before his birth. The duchess also talked about the intense isolation she felt inside the royal family that led her to contemplate suicide.

Harry's highly anticipated memoir, titled "Spare," is coming out on Jan. 10.

The Associated Press contributed to this report.