The UK has long been one of the United States' closest allies, from President Franklin Delano Roosevelt and Prime Minister Winston Churchhill during World War 2 to President Ronald Reagan and Tory Prime Minister Margaret Thatcher during the 1980s to President George W. Bush and Labour Prime Minister Tony Blair after the 9/11 terrorist attacks. But according to the UK-based i Paper, King Charles III was privately "jittery" about U.S. President Donald Trump's most recent trip to the UK.
Trump visited the UK in September 2025, meeting with King Charles, Queen Camila and Labour Prime Minister Keir Starmer. And King Charles, visiting Washington, DC in late April 2026, gave an historic speech during a joint session of Congress.
Journalist Caroline Wheeler, Jane Merrick and Arj Singh, reporting for the i Paper, explain, "The King raised serious concerns about Donald Trump's state visit to the UK in the wake of the U.S. president's infamous bust-up with (Ukrainian President) Volodymyr Zelensky, the i Paper understands. The monarch's private reservations over the visit left officials scrambling, fearful that a royal snub of President Trump could detonate into a full-blown diplomatic crisis. Multiple senior Whitehall sources have told this newspaper that the King was reticent about hosting Trump at this time because of his treatment of Zelensky."
An i Paper source told the British publication that King Charles was "jittery" about meeting with Trump, and another source said that he "did not want to do it."
This "revelation," according to Wheeler, Merrick and Singh, "illustrates how fraught UK-U.S. diplomatic relations have been during Trump's time in office" and also underscores King Charles' "unique role as the bridge between No. 10 (Downing Street) and the White House."
"A flurry of e-mails and texts exchanged between Peter Mandelson, then U.S. ambassador, and officials in March 2025 reveal a behind-the-scenes diplomatic scramble to alleviate Charles' concerns over the visit," the i Paper reporters note. "In one message, the peer thanks the most senior civil servant in Foreign Office for his 'cool handling of the last 48 hours on the SV (state visit)' — and in another exchange five days later, Mandelson discusses how he is awaiting an update following the weekly audience between the King and Prime Minister Sir Keir Starmer. It highlights the diplomatic tightrope being walked by the UK amid fears that the U.S. president could pull America's support for Ukraine completely following his clash with Zelensky in the Oval Office at the end of February last year."
Wheeler, Merrick and Singh continue, "The King's concerns are understood to be included in a number of heavily redacted documents released in the so-called Mandelson files, which contained hundreds of private WhatsApp messages and e-mail exchanges between the peer and current and former Cabinet ministers, senior civil servants and advisers…. The messages which have been published indicate that officials and diplomats were working intensively behind the scenes to allay the King's concerns, and suggest that Starmer was due to discuss them with Charles at their weekly audience."