Donald Trump appeared to break royal protocol during a meeting with the Prince and Princess of Wales at Windsor Castle — but a lip reader claims to have uncovered exactly what the former U.S. president said in the moment.

Trump, 79, and his wife Melania, 55, are currently in the UK for their second state visit, having landed at London Stansted Airport on Monday, September 16. On Tuesday, September 17, the couple flew by helicopter onto the grounds of Windsor Castle, where they were greeted by Prince William and Kate Middleton before meeting King Charles III and Queen Camilla.

The arrival, however, did not go according to plan. The helicopter had been scheduled to land at 11:55 a.m., but only began circling the gardens around 12:10 p.m. before touching down at 12:14. Trump stepped out at 12:15, pushing back the royal timetable by nearly 20 minutes.

When greeting the royals, Trump shook hands with both William and Kate. Observers noticed two small gestures that sparked debate online: he appeared to give Kate’s hand a slight pull, and then gave William a friendly tap on the shoulder — something not typically done during formal royal greetings.