The Queen rolled out the red carpet for the President at Buckingham Palace at the start of his three-day state visit.
But a grumpy looking Harry, 34, kept as far away as possible.
Meghan had backed Trump’s Democrat rival Hilary Clinton during the 2016 election, and said she would move to Canada if he won.
He and wife Melania landed at Stansted Airport, Essex, at 8:56 a.m. following an overnight flight on Air Force One from Washington DC.
They later boarded their Marine One helicopter and were flown to central London — landing on the Palace lawn at 12:12 pm.
Harry attended the private lunch with Donald and First Lady Melania, but on a tour of Her Majesty’s private art collection hung back and did not want to be photographed with any of the party.
He walked in with the President’s daughter Ivanka but left her to talk to the Lord Chamberlain while the Queen showed the Trumps around with Prince Charles close behind.
An onlooker said: “Harry was the third most senior royal in the room after the Queen and his father, but didn’t seem to take any part in his royal duties.”
Royal commentator Ingrid Seward said: “Harry did look grumpy and as if he didn’t want to be there.
“He appears to be behaving in a rather immature way and letting his personal animosity take over from his natural good manners.
“Whatever his personal feelings, it’s his duty to support the Queen regardless and take a tip from his grandmother who has never allowed her personal feelings to interfere with her duty.
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